UEPAUTMKXT OF THE INTKKIOR

BULLETIN

OP THK

UNITED STATES

No. 1O3

HIGH TEMPERATURE WORK IX IGNEOUS FUSION AND 

EBULLITION, CHIEFLY IN RELATION 

TO PRESSURE

WASH I NOTON

GOVERNMENT PRINTING OFFICE 

1893

LIBRARY CATALOGUE SLIPS.

United States. Department of the interior. (U. S. geological survey). 

Department of the interior | | Bulletin | of the | United 

States | geological survey | no. 103 | [Seal of the department] | 

Washington | government printing office | 1893

Second tillv: United States geological snrvey | J. W. Powell, 

director | | High temperature work | in | igneous fusion and 

ebullition | chiefly in relation to pressure | by | Carl Bams | 

[Vignette] | jj

AVashingtou | government printing officeV| 1893

8°. 57pp. 9 pi. *

Barus (Carl).

United States geological survey | J. W. Powell, director | | 

High temperature work | in | igneous fusion and ebullition | 

chiefly in relation to pressure | by | Carl Barus | [Vignette] |

Washington | government printing office | 1893

8°. 57 pp. 9 pi.

[UNITED STATES. Department of the interior. (U. S. geological survey). 

Bulletin 103.]

United States geological survey | J. W. Powell, director | | 

High temperature work | in | igneous fusion and ebullition | 

chiefly in relation to pressure | by | Carl Barus | [Vignette] |

Washington | government printing office | 1893

8°. 57 pp. 9 pi.

[UNITED STATES. Department of the interior. (17. S. geological survey). 

Bulletin 103..]

[Bulletin No. 103.]

The publications of the United States Geological Survey are issued in accordance with the statute 

approved March 3, 1879, which declares that 

'' The publications of the Geological Survey shall consist of the annual report of operations, geological 

and economic maps illustrating the resources and classification of the lands, and reports upon general 

and economic geology and paleontology. The annual report of operations of the Geological Survey 

shall accompany the annual report of the Secretary of the Interior. All special memoirs and reports 

of said Survey shall bo issued in uniform quarto series if deemed necessary by the Director, but otherwise in ordinary octavos. Throe thousand copies of each shall bo published for scientific exchanges 

and for sale at the price of publication; and all literary and cartographic materials received in exchange 

shall be the property of the United States and form a part of the library of the organization; and the 

money resulting from the sale of such publications shall be covered into the Treasury of the United 

States."

On July 7, 1882, the following joint resolution, referring to all Government publications, was passed 

by Congress:

"That whenever any document or report shall bo ordered p'rinted by Congress, there shall be printed, 

in addition to the number in each case stated, the 'usual number' (734) of copies for binding and 

distribution among those entitled to receive them."

Except in those cases in which an extra number of any publication has been supplied to the Survey 

by special resolution of Congress or has been ordered by the Secretary of the Interior, this ollice has 

no copies for gratuitous distribution.

ANNUAL REPORTS.

I. First Annual Report of the United States Geological Survey, by Clarence King. 1880. 8°. 79 pp. 

1 map. A preliminary report describing plan of organization and publications.

II. Second Annual Report of the United States Geological Survey, 1880-'81, by J. W. Powoll. 1882. 

8°. Iv, 588pp. 62 pi. Imap.

in. Third Annual Report of the United States Geological Survey, 1881-'82, by J. W. Powell. 1883. 

8°. xviii, 504 pp. 07 pi. and maps.

IV. Fourth Annual Report of the United States Geological Survey, 1882-'83, by J. W. Powell. 1884. 

8°. xxxii, 473 pp. 85 pi. and maps.

V. Fifth Annual Report of the United States Geological Survey, 1883-'84, by J. W. Powell. 1885. 

8°. xxxvi, 409 pp. 58 pi. and maps.

VI. Sixth Annual Report of the United States Geological Survey, 1884-'85, by J. W. Powell. 1885. 

8°. xxix, 570 pp. 65 pi. and maps.

VII. Seventh Annual Report of the United States Geological Survey, 1885-'86, by J. W. Powoll. 1888. 

8°. xx, 056 pp. 71 pi. and maps.

VIII. Eighth Annual Report of the United States Geological Survey, 1886-'87, by J. W. Powell. 1889. 

8°. 2pt. xix, 474, xii pp. 53 pi. and maps; 1 p. 1., 475-10C3 pp. 54-76 pi. and maps.

IX. Ninth Annual Report of the United States Geological Survey, 1887-'88, by J. W. Powell. 1889. 

8°. xiii, 717 pp. 88 pi. and maps.

X. Tenth Annual Report of the United States Geological Survey, 1888-'89, by J. "W. Powell. 1890. 

8°. 2pt. xv, 774 pp. 98 pi. and maps; viii, 123 pp.

XI. Eleventh Annual Reportof the United States Geological Survey. 1889-'90, by J. W. Powoll. 1891. 

8°. 2pt. xv, 757pp. 00 pi. and maps; ix, 351 pp. 30 pi.

XII. Twelfth Annual Report of the United States Geological Survey, 1890-'91. by J. W. Powell. 1891. 

8°. 2pt. xiii, 675 pp. 53 pi. and maps; xviii, 576 pp. 146 pi. and imips.

XIII. Thirteenth Annual Report of the United States Geological Survey, 1891-:92, by J. "W. Powell, 

1893. 8°. 3 pt.

MONOGRAPHS.

I. Lake Bonnoville, by Grove Tvarl Gilbert. 1890. 4°. xx, 438 pp. 51 pi. 1 map. Price $1.50.

II. Tertiary History of the Grand Cation District, with atlas, by Clarence E. Button, Copt. U. S. A. 

1882. 4°. xiv, 2C4 pp. 42 pi. and atlas of 24 shr^ts folio. Price $10.00.

I
II ADVERTISEMENT.

HI. Geology of tlie Comstock Lode and the Washoe District, with atlas, by George F. Becker. 1882. 

4°. xy, 422 pp. 7 pi. and atlas of 21 sheets folio. Price $11.00.

IV. Comstock Mining and Miners, by Eliot Lord. 1883. 4°. xiv, 451 pp. 3 pi. Price $1.50.

V. The Copper-Bearing Eocks of Lake Superior, by Eolaud Drier Irving. 1883. 4°. xvi, 464 pp. 

151. 29 pi. and maps. Price $1.85.

VI. Contributions to the Knowledge of the Older Mosozoic Flora of Virginia, by William Morris 

Fontaine. 1883. 4°. xi, 144 pp. 541. 54 pi. Price $1.05.

VII. Silver-Lead Deposits of Eureka, Nevada, by Joseph Story Curtis. 1884. 4°. xiii, 200 pp. 16 

pi. Price $1.20.

Vm. Paleontology of the Eureka District, by Charles Doolittle Walcott. 1884. 4°. xiii, 298 pp. 

241. 24 pi. Price $1.10.

IX. Brachiopoda and Lamellibranchiata of the Earitan Clays and Greensand Marls of New Jersey, 

by Eobert P. Whitfield. 1885. 4°. xx, 338 pp. 35 pi. Imap. Price $1.15.

X. Dinocerata. A Monograph of an Extinct Order of Gigantic Mammals, by Othniel Charles Marsh 

1886. 4°. xviii, 243 pp. 561. 56 pi. Price $2.70.

XI. Geological History of Lake Lahoutan, a Quaternary Lake of Northwestern Nevada, by Israel 

Cook Russell. 1885. 4°. xiv, 288 pp. 46 pi. and maps. Price $1.75.

XH. Geology and Mining Industry of Leadville, Colorado, with atlas, by Samuel Franklin Emmons. 

1886. 4°. xxix, 770pp. 45 pi. and atlas of 35 sheets folio. Price $8.40.

XIII. Geology of the Quicksilver Deposits of the Pacific Slope, with atlas, by George F. Becker, 

1888. 4°. xix, 486 pp. 7 pi. and atlas of 14 sheets folio. Price $2.00.

XIV. Fossil Fishes and Fossil Plants of the Triassic Eocks of New Jersey and the Connecticut Valley, by John S. Newberry. 1888. 4°. xiv, 152 pp. 26 pi. Price $1.00.

XV. The Potomac or Younger Mesozoic Flora, by "William Morris Fontaine. 1889. 4°. xiv, 377 

pp. 180 pi. Text and plates bound separately. Price $2.50.

XVI. The Paleozoic Fishes of North America, by John Strong Newberry. 1889. -4°. 340pp. 53 pi. 

Price $1.00.

XVH. The Flora of the Dakota Group, a posthumous work, by Leo Lesquoreux. Edited by F. H. 

Knowlton. 1891. 4°. 400pp. 66 pi. Price $1.10.

XVIII. Gasteropoda and Cephalopoda of the Earitan Clays and Greensand Marls of New Jersey, 

by Eobert P. WhitfieM. 1891. 4°. 402pp. 50 pi. Price $1.00.

XIX. The Penokee Iron-Bearing Series of Northern Wisconsin and Michigan, by Eoland D. Irving 

and C. E. Van Hise. 1892. 4°. xix, 534pp. 37 pi.

XX. Geology of the Eureka District, Nevada, with atlas, by Arnold Hague. 1892. 4°. 419 pp. 8 pi. 

In press:

XXI. The Tertiary Ehynchophorous Coleoptera of North America, by Samuel Hubbard Scudder.

XXII. A Manual of Topographic Methods, by Henry Gannett, chief topographer.

XXUI. Geology of the Green Mountains in Massachusetts, by Eaphael Pumpelly, J. E. Wolff, 

T. Nelson Dale, and Bayard T. Putnam. 

In preparation:

 Mollusca and Crustacea of the Miocene Formations of New Jersey, by E. P. Whitfield.'

 Sauropoda, by 0. C. Marsh.

 Stegosauria, by 0. C. Marsh.

 Brontothcridte, by 0. C. Marsh.

 Eeport on the Denver Coal Basin, by S. F. Emmons.

 Eeport on Silver Cliifand Ten-Mile Mining Districts, Colorado, by S. F. Emraons.

 The Glacial Lake Agassiz, by Warren tjpham.

BULLETINS.

1. On Hypersthene-Ahdesite and on Triclinic Pyroxene in Augitic Eocks, by Whitman Cross, with a 

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4. On Mesozoic Fossils, by Charles A. White. 1884. 8°. 36 pp. 9 pi. Price 5 cents.

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6. Elevations in the Dominion of Canada, by J. W. Spencer. 1884. 8°. 43pp. Price 5 cents.

7. Mapoteca Geologica Americana. A Catalogue of Geological Maps of America (North and South), 

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8. On Secondary Enlargements of Mineral Fragments in Certain Eocks, by E. D. Irving and C. E. 

Van Hise. 1884. 8°. 56 pp. 6 pi. Price 10 cents.

9. A report of work done in the Washington Laboratory during'the fiscal year 1883-'84. F. W. Clarke, 

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ADVERTISEMENT. Ill

10. On the Cambrian Faunas of North America. Preliminary studies, hy Charles Doolittlo AValcott. 

1884. 8°. 74pp. 10 pi. Price 5 cents.

11. On the Quaternary and Recent Mollusca of the Great Basin; with Descriptions of New Forms. 

by R. Ellsworth Call. Introduced by a sketch of the Quaternary Lakes of the Great Basin, by G. K. 

Gilbert. 1884. 8°. 06 pp. 6 pi. Price 5 cents.

12. A Crystallographic Study of the Thinolitc of Lake Lahontan, by Edward S. Dana. 1884. 8°. 

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13. Boundaries of the United States and of the several States and Territories, with a Historical 

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14. Tho Electrical and Magnetic Properties of the Iron-Carburets, hy Carl Barns and Vincent 

Strouhal. 1885. 8°. 238 pp. Price 15 cents. -

15. On the Mesozoic and Ceuozoic Paleontology of California, by Charles A. White. 1885. 8°. 83 pp. 

Price 5 cents.

1C. On the Higher Devonian Faunas of Ontario County, New York, by John M. Clarko. 1885. 8°. 

86 pp. 3 pi. Price 5 cents. 

17. On the Development of Crystallization in the Igneous Rocks of Washoe, Nevada, with nol.os on 

the Geology of the District, by Arnold Hague and'Joseph P. Iddinga. 1885. 8°. 44 pp. Price 5 

cents.

18. On Marino Eocene, Fresh-water Miocene, and other Fossil Mollusca of Western Nortli America, 

by Charles A. White. 1885. 8°. 20 pp. 3 pi. Price 5 cents.

19. Notes on the Stratigraphy of California, by George F. Beckcr. 1885. 8°. 28 pp. Price 5 cents.

20. Contributions to the Mineralogy of the Rocky Mountains, by AVhitnian Cross and \V. F. Hillebrand. ISs's. 8°. 114 pp. 1 pi. Price 10 cents.

21. The Lignites of the Great Sioux Reservation. A Report on the Region between the Grand and 

Moreau Rivers, Dakota, by Bailey Willis. 1885. 8°. 16pp. 5 pi. Price 5 cents. '

22. On Now Cretaceous Fossils from California, by Charles A. White. 1885. 8°. 25 pp. 5 pi. 

Price 5 cents.

23. Observations on the Junction between the Eastern Sandstone and the Kewecnaw Scries on Keweenaw Point, Lake Superior, by R. D. Irving and T. C. Chamberlin. 1885. 8°. 124 pp. 17 pi. 

Price 15 cents.

24. List of Marino Mollusca, comprising the Quaternary Fossils and recent forms from American 

Localities between Capo Hatteras and Cape Roque, including the Bermudas, by William Healy Dall. 

1885. 8°. 336 pp. Price 25 cents.

25. The Present Technical Condition of the Steel Industry of the United States, by Phineas Barnes. 

1885. 8°. 85 pp. Price 10 cents.

26. Copper Smelting, by Henry M. Howe. 1885. 8°. 107 pp. Price 10 cents.

27. Report of work done in the Division of Chemistry and Physics, mainly during the fiscal year

1884-'85. 1886. 8°. 80 pp. Price 10 cents. I

28. The Gabbros and Associated Hornblende Rocks occurring in the neighborhood of Baltimore, 

Md., by George Hnntiugton Williams. 1886. 8°. 78 pp. 4 pi. Price 10 cents. 

29. On the Fresh-water Invertebrates of the North American Jurassic, by Charles A. White. 1880. 

8°. 41 pp. 4 pi. Price 5 cents.

30. Second Contribution to the Studies on the Cambrian Faunas of North America, by Charles Doolittlo Walcott. 1886. 8°. 309 pp. 33 pi. Price 25 cents.

31. Systematic Review of our Present Knowledge of Fossil Insects, including Myriapods and Arachnids, by Samuel Hubbard Scudder. 1886. 8°. 128 pp. Price 15 cents.

32. Lists and Analyses of the Mineral Spriugs'of the United States; a Preliminary Study, by Albert 

C. Peale. 1886. 8°. 235 pp. Price 20 cents. 

33. Notes on the Geology of Northern California, by J. S. Diller. 1886. 8°. 23 pp. Price 5 cents.

34. On the relation of the Laramie Molluscan Fauna to that of the succeeding Fresh-water Eocene 

and other groups, by Charles A; White. 1886. 8°. 54 pp. 5 pi. Price 10 cents.

35. Physical Properties of the Iron-Carburets, by Carl Barns and "Vincent Strouhal. 1886. 8°. 62 

pp. Price 10 cents.

36. Subsidence of Fine Solid Particles in Liquids, by Carl Barns. 1886. 8°. 58 pp. Price 10 cents.

37. Types of the Laramie Flora, by LesterF. Ward. 1887. 8°. 354pp. 57 pi. Price 25 cents.

38. Peridotito of Elliott County, Kentucky, by J. S. Diller. 1887. 8°. 31pp. 1 pi. Price 5 cents.

39. The.Upper Beaches and Deltas of the Glacial Lake Agassiz, by Warren Upham. 1887. 8°. 84 

pp. 1 pi. Price 10 cents.

40. Changes in River Courses in Washington Territory clue to Glaciation, by Bailey Willis. 1887. 

8°. 10pp. 4 pi. Price 5 cents.

41. On the Fossil Faunas of the Upper Devonian the Geneseo Section, Now York, by Henry S. 

Williams. 1887. 8°. 121pp. 4 pi. Price 15 cents.

42. Report of work done ^iu the Division of Chemistry and Physics, mainly during the fiscal year

1885-'86. F. W. Clarke, chief chemist. 1887. 8°. 152 pp. 1 pi. "Price 15 cents.

43. Tertiary and Cretaceous Strata of tho Tnscaloosa, Tombigbee, and Alabama Rivers, by Eugene 

A. Smith and Lawrence C. Johnson. 1887. 8°. 189pp. 21 pi. Price 15 cents.

44. Bibliography of North American Geology for 1886, by Nelson H. Darton. 1887. 8°. 35 pp. 

Price 5 cents.
IV ADVERTISEMENT.

45. The Present Condition of Knowledge of the G eology of Texas, by Eobert T. Hill. 1887. 8°. 94 

pp. Price 10 cents.

46. Nature and Originl»f Deposits of Phosphate of Lime, by R. A. E. Penrose, jr., with an Introduction by N.S. Shaler. 1888. 8°. 143pp. Price 15 cents.

47. Analyses of Waters of the Tellowstone National Park, with an Account of the Methods of 

Analysis employed, by Erank Austin Gooch and James Edward "Whitfleld. 1888. 8°. 84 pp. Price 

10 cents.

48. On the Eorm and Position of the Sea Level, by Robert Simpson "Woodward. 1888. 8°. 88pp. 

Price 10 cents.

49. Latitudes and Longitudes of Certain Points in Missouri, Kansas, and New Mexico, by Robert 

Simpson Woodward. 1889. 8°. 133 pp. Price 15 cents. v

50. Formulas and Tables to facilitate the Construction and Use of Maps, by Robert Simpson Woodward. 1889. 8°. 124pp. Price 15 cents.

51. On Invertebrate Eossils from the Pacific Coast, by Charles Abiathar White. 1889. 8°. 102 pp. 

14 pi. Price 15 cents.

52. Subaerial Decay of Rocks and Origin of the Red Color of Certain Formations, by Israel Cook 

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53. The Geology of Nantucket, by Nathaniel Southgate Shalor. 1889. 8°. 55pp. 10 pi. Price 10 

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54. On the Thenno-Electric Measurement of High Temperatures, by Carl Barus. 1889. 8°. 313 pp. 

incl. 1 pi. 11 pi. Price 25 cents.

55. Report of work done in the Division of Chemistry and Physics, mainly during the. fiscal year 

1886-'87. Erauk Wigglesworth Clarice, chief chemist. 1889. 8°. 96pp. Price 10 cents.

56. Fossil Wood and Lignite of the Potomac Formation, by Frank Hall Kuowlton. 1889. 8°. 72pp. 

7 pi. Price 10 cents.

57. A Geological Reconnaissance in Southwestern Kansas, by Robert Hay. 1890. 8°. 49 pp. 2 pi. 

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58. The Glacial Boundary in Western Pennsylvania, Ohio, Kentucky, Indiana, and Illinois, by George 

Frederick AVright, with an introduction by Thomas Chrowder Chamberlin. 1890. 8°. 112 pp. incl. 

1 pi. 8 pi. Price 15 cents.

59. The Gabbros and Associated Rocks in Delaware, by Frederick D. Chester. 1890. 8°. 45 pp. 

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60. Report of work done in the Division of Chemistry and Physics, mainly during the fiscal year 

1887-'88. F. W. Clarkc, chief chemist. 1890. 8°. .174 pp. Price 15 cents.

Cl. Contributions to the Mineralogy of the Pacific Coast, by William Harlow Melville and Waldemar 

Lindgren. 1890. 8°. 40 pp. 3 pi. Price 5 cents.

62. The Greenstone Schist Areas of the Menomiueo and Marquetto Regions of Michigan; a contri 

bution to the subject of dynamic metamorpbism in eruptive rocks, by George Huntingtou Williams; 

with an introduction by Roland Duer Irving. 1890. 8°. 241 pp. 16 pi. Price 30 cents.

63. A Bibliography of Paleozoic Crustacea from 1698 to 1889, including a list of North American 

species and a systematic arrangement of genera, by Anthony W. Vogdos. 1890. 8°. 177 pp. Price 

15 cents.

64. A report of work done in the Division of Chemistry and Physics, mainly during the fiscal year 

1888-'89. F. W. Clarke, chief chemist. 1890. 8°. CO pp. Price 10 cents.

65. Stratigraphy of the Bituminous Coal Field of Pennsylvania, Ohio, and West Virginia, by Israel 

C. White. 1891. 8°. 212 pp. 11 pi. Price 20 cents.

66. On a Group of Volcanic Rocks from the Tewan Mountains, New Mexico, and on the occurrence 

of Primary Quartz in certain Basalts, by Joseph* Paxson Iddings. 1890. 8°. 34pp. Price 5 cents.

67. The Relations of the Traps of the Newark System in the New Jersey Region, by Nelson Horatio 

Darton. 1890. 8°. 82 pp. Price 10 cents.

68. Earthquakes in California in 1889, by James Edward Keoler. 1890. 8°. 25 pp. Price 5 cents.

69. A Classed and Annotated Bibliography of Fossil Insects, by Samuel Hnbbard Scudder. 1890. 

8°. 101 pp. Price 15 cents.

70. Report on Astronomical Work of 1889 and 1890, by Robert Simpson Woodward. 1890. 8°. 79pp. 

Price 10 cents.

71. Index to the Known Fossil Insects of the World, including Myriapods and Arachnids, by Samuel 

Hubbard Scudder. 1891. 8°. 744 pp. Price 50 cents.

72. Altitudes between Lake Superior and the Rocky Mountains, by Warren TJpbam. 1891. 8°. 

229 pp. Price 20 cents.

73. The Viscosity of Solids, by Carl Barus. 1891. 8°. xii, 139 pp. 6 pi. Price 15 cents.

74. The Minerals of North Carolina, by Frederick Augustus Genth. 1891. 8°. 119 pp. Price 15 

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75. Record of North American Geology for 1887 to 1889, inclusive, by Nelson Horatio Darton. 1891. 

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76. A Dictionary of Altitudes in the United States (second edition), compiled by Henry Gannett, 

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77. The Texan Permian and its Mesozoic Types of Eossils, by Charles A. White. 1891. 8°. 51 pp. 

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ADVERTISEMENT. V

78. A report of work done in the Division of Chemistry and Physics, mainly during the fiscal year 

1889-'90. F. W. Clarko, chief chemist. 1891. 8°. 131pp. Price 15 cents.

 79. A Lato Volcanic Eruption in Northern California and its Peculiar Lava, by J. S. Diller. 1891. 8°. 

33pp. 17 pi. Price 10 cents.

80. Correlation papers Devonian and Carboniferous, by Henry Shaler Williams. 1891. 8°. 279pp. 

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81. Correlation papers Cambrian, by Charles Doolittlo Walcott. 1891. 8°. 447 pp. 3 pi. Price 

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82. Correlation papers Cretaceous, by Charles A. White. 1891. 8°. 273 pp. 3 pi. Price 20 cents. 

'. 83. Correlation papers Eocene, by William Bullock Clark. 1891. 8°. 173pp. 2 pi. Price 15 cents.

84. Correlation papers Neocene, by W. H. Dall and G-. D. Harris. 1892. 8°. 349 pp. 3 pi. Price 

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85. Correlation papers The Newark System, by Israel Cook Bussell. 1892. 8°. 344 pp. 13 pi. 

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80. Correlation papers Archean and Algonkian, by C. E. Van Hiso. 1892. 8°. 549 pp. 12 pi. 

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90. A report of work done in the Division of Chemistry and Physics, mainly duriug tho fiscal year 

1890-'91. F. W. Clarke, chief chemist. 1892. 8°. 77pp. Price 10 cents.

91. Eocord of North American Geology for 1890, by Nelson Horatio Darton. 1891. 8°. 88 pp. Price 

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92. The Compressibility of Liquids, by Carl Barus. 1892. 8°. 96pp. 29 pi. Price 10 cents.

93. Some insects of special interest from Florissant, Colorado, and other points in the Tertiariea of 

Colorado and Utah, by Samuel Hubbard Scudder. 1892. 8°. 35 pp. 3 pi. Price 5 cents.

94. The Mechanism of Solid Viscosity, by Carl Barus. 1892. 8°. 138pp. Price 15 cents.

95. Earthquakes in California in 1890 and 1891, by Edward Singleton Holdon. 1892. 8°. 31 pp. 

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96. The Volume Thermodynamics of Liquids, by Carl Barns. 1892. 8°. 100pp. Price 10 cents.

97. The Mesozoic Echiuodermata of the United States, by W. B. Clark. 1893. 8°. 207 pp. 50 pi. 

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98. Flora of tho Outlying Carboniferous Basins of Southwestern Missouri,by David White. 1893. 8°. 

139 pp. 5 pi. Price 15 cents.

99. Eocord of North American Geology for 1891, by Nelson Horatio Dartou. 1892. 8°. 73 pp. 

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100. Bibliography and Index of tho publications of tho U. S. Geological Survey, 1879-1892, by Philip

 Groveling Warman. 8°. 495pp. Price 25 cents.

101. Insect Fauna of the Rhode Island Coal Field, by Samuel Hubbard Scudder. 1893. 8°. 27pp. 

2 pi. Price 5 cents.

103. High Temperature Work in Igneous Fusion and Ebullition, chiefly in relation to pressure, by 

Carl Barus. 1893. 8°. 57pp. 9 pi. Price 10 cents.

104. Glaciation of tho Yellowstoue Valley north of tho Park, by W. H. Weed. 1893. 8°. 41 pp. 

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105. Tho Lararaio and tho overlying Livingston Formation in Montana, by Walter Harvey AVeod,

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106. Tho Colorado Formation and its Invertebrate Fauna, by T. W. Stantou. 1893. 8°. 288 pp. 

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108. A Geological Eoconnoissanco in Central Washington, by Israel Cook Kussell. 1893. 8°. ]08pp. 

12 pi. Price 15 cents.

In press:

102. A Catalogue and Bibliography of North American Mesozoic Invertobrata, by C. B. Boyle. 

107. Tho Trap Dikes of Lake Champlain Valley and the Eastern Adirondacks, by J. F. Kemp.

109. Tho Eruptive .and Sedimentary Eocks on Pigeon Point, Minnesota, and their contact phenomena, by W. S. Bayley.

110. Tho Paleozoic Section in tho vicinity of Three Forks, Montana, by A. C. Pealc. 

In preparation:

 The Moraines of the Missouri Cotcau, anil their attendant deposits, by James Edward Todd.

 On the Structure of the llidgo between tho Taconic and tho Green Mountain Kanges in Vermont; and Ou tho Structure of Monument Mountain in Great Barringtou, Mass., by T. Nelson Dale.

 ' A Bibliography of Paleobotany, by David White.

STATISTICAL PAPEES.

Mineral Resources of tho United States, 1882, by Albert Williams, jr. 1883. 8°. xvii, 813 pp. Price 

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Mineral Resources of tho United States, 1883 and 1884, by Albert Williams, jr. 1885. 8°. xiv, 1016 

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Mineral Eosourccs of tho United States, 1885. Division of Mining Statistics and Technology. 1886. 

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VI ADVERTISEMENT,

Mineral Kesources of the United States, 1886, by David T. Day. 1887. 8°. viii, 813pp. Price 50 cents.

Mineral Resources of the United States, 1887, by David T. Day. 1888. 8°. vii,832pp. Price 50 cents.

Mineral Kesources of the United States, 1888, by David T. Day. 1890. 8°. vii, 952 pp. Price 50 cents.

Mineral Eesources of the United States, 1889 and 1890, by David T. Day. 1892. 8°. viii, 071 pp. 

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Mineral Kesources of the United States, 1891, by David T. Day. 1893. 8°. vii, 630pp. Price 50 cents. 

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Mineral Kesources of the United States, 1892.

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To THE DIRECTOR OF THE

UNITED STATES GEOLOGICAL SURVEY,

WASHINGTON, D. C.

WASHINGTON, D. C., September, IMS.
DEPARTMENT OF THE INTERIOR

BULLETIN

UNITED STATES

GEOLOGICAL SURVEY

]STo. 1O3

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1893

UNITED STATES GEOLOGICAL SURVEY

J. W. POWELL, DIRECTOR

HIGH TEMPEEATUEE WOEK

CHIEFLY IN RELATION TO PRESSURE

CARL BARUS

'WASHINGTON

" GOVERNMENT PRINTING- OFFICE 

1803

CONTENTS.

Page.

Preface..................................................................... 9

CHAPTER I. The pressure variations of certain high temperature (metallic)

boiling points............................................. 11

Introductory............................................................ 11

The plan pursued ................................................... 11

The pyrometer ....................................................... 12

Apparatus .............................................................. 12

Low boiling points.................................................. 12

High boiling points................................................. 13

Torsion galvanometer. .... I.^....................................... 14

Cold junction....................................................... 16

Observations ........................................................... 10

Mercury ............................................................ 10

Sulphur ............................................................ 18

Zinc................................................................ 19

Cadmium. .......................................................... 19

Bismuth............................................................ 20

Remarks............................................................ 21

Inferences.............................................................. 21

Available equations................................................. 21

Constants computed ................................................ 22

Graphic representation ............................................... 23

Conclusion.......................................................... 23

CHAPTER II. The contraction of molten igneous rgck on passing from liquid to

solid ..................................................... 25

Introductory............................................................ 25

Th e r o ck............................................................ 25

Literature.......................................................... 25

Effect of fusion (polyinerisui)........................................ 25

Apparatus.............................................................. 27

Temperature measurement .......................................... 27

General disposition of apparatus .................................... 28

Furnace ............................................................ 29

Fusion tube ........................................................ 3Q

Thermocouples...................................................... 30

Sight tubes ......................................................... . 31

Vertical micrometer................r*................................ 31

Telephonic registration ............................................. 32

Method of measurement................................................. 33

Consecutive adjustments............................................ 33

Computation........................................................ 34

Errors .............................................................. 35

5
6 CONTENTS.

CHAPTER II Continued. c Page.

Eesults................................................................. 37

Arrangement of the tables .......................................... 37

Contraction of diabase. Tables..................................... 37

Contraction of diabase. Tables and chart..............1............ 39

Contraction of diabase. Tables and chart........................... 40

General remarks .................................................... 41

Fusion and solidification alternating ................................ 42

Inferences .............................................................. 43

Comparison with thymol............................................ 43

Lower critical temperature...................... .... ................ 43

Melting point and pressure.......................................... 44

CHAPTER III. The thermal capacity of igneous rock, considered in its bearing on melting point and pressure........................ 45

Preliminary remarks.................................................... 45

Introductory........................................................ 45

Literature .......................................................... 45

Apparatus .............................................................. 46

The rock to be tested ............................................... 46

Thermal capacity of platinum....................................... 46

Furnace ............................................................ 46

Temperature........................................................ 47

Calorimeter......................................................... 48

Results................................................................. 48

Method of work..................................................... 48

Arrangement of the tables .......................................... 49

Tables.............................................................. 49

Inferences ........................C...................................... 53

Digest and charts ................................................... 53

Specific heat........c............................................... 54

Hysteresis .............................................. ............ 54

Latent heat................................................ .^....... 54

The relation, of melting point to pressure .....................--.- - 55
ILLUSTRATIONS.

Pago. 

PLATE I. Boiling tube and appurtenances for low temperature............... 12

II. Torsion galvanometer for thermoelectric p.yrometry ................. 14

III. Chart showing the change of boiling point with pressure (centimeters of mercury) for water, mercury, sulphur, cadmium, zinc, and 

bismuth....................................................... 24

IV. Furnace for measuring volume contraction of molten rock.......... 30

V. Contraction of molten diabase, continuously from liquid to solid... 40

VI. Contraction of molten diabase, continuously from liquid to solid..... 42

VII. Furnace for calorimotry, with the body (crucible), the pyrometer

and the holders in place ...................................... 46

VIII. Relation of thermal capacity (solid and liquid) to temperature (°C.). 52

IX. Relation of thermal capacity (solid and liquid) to temperature (°C.). 54

FIG. 1. Boiling crucible for high temperatures............................... 12

2. Furnace Avith crucible in place ...................................... 13

3. Cyclic volume changes produced by alternate fusion and solidification

of rock magma (diabase)........................................... 43

7

PREFACE.

In the following bulletin I have brought together .the more important results of experiments in high temperatures, made since the publication of my bulletin on the thermoelectric measurement of high 

temperatures. 1 Chapter I, in addition to pointing out certain inherent 

relations between metallic vapor tensions, has a direct bearing on 

pyroinetry. Chapters 11 and in are of geological importance, and the 

work was done for Mr. Clarence King. Chapter n shows that in case 

of the igneous fusion of basic magma, the passage from liquid to solid 

is one of contraction, and measures the difference of specific volumes at 

the solidifying temperature. Chapter in contains a full account of the 

thermal capacity of the same rock under the same conditions, and by 

aid of Chapter n levels to a numerical value for the relation of melting 

point to pressure, for silicates.

CARL BARTJS.

JUNE 8,1892.

'Bull. U. S. Geol. Survey, No. 54, 1889, p. 313. '

HIGH TEMPERATURE WORK IN IGNEOUS FUSION AND EBULLITION, CHIEFLY IN RELATION TO PRESSURE.

BY CARL BARUS.

CHAPTBE I.

THE PRESSURE VARIATIONS OF CERTAIN HIGH TEMPERATURE

(METALLIC) BOILING POINTS. 1

t

INTRODUCTORY.

1. The plan pursued. In the following chapter 2 1 describe a practical 

method for the calibration of thermocouples by aid of boiling points, 

and then apply it in measuring the vapor tensions of zinc, cadmium, 

and bismuth. During the course of the work a much neglected principle of Groshans 3 is advantageously employed. I must state at the out 

set that it is not at all my object to furnish accurate values for boiling 

points. The purpose of this paper is to investigate the probable nature 

of the relation of boiling point to pressure, throughout very wide ranges 

of temperature, with the hope of stimulating speculation on the subject somewhat more rigorous than that of Groshans. It is clear, that if 

a law can be found by which the normal (76 centimeters) boiling point 

of a substance can be predicted from an observed low-pressure boiling 

point, then there is hope of arriving at a more complete knowledge of 

high-temperature boiling points than is now available. More than this: 

By varying pressure, boiliDg points may be made to overlap each other. 

Hence a thermocouple calibrated as far as the boiling point of zinc for 

instance, may be used to measure the low-pressure boiling point of 

bismuth (say), and the couple then may be further calibrated by making 

use of the normal boiling point of bismuth at 76 centimeters, predicted 

by aid of the law in question. The process may obviously be repeated. 

The couple whose.calibration interval has been enlarged in the manner 

given, may now be used to fix the low-pressure boiling point of some

1 The literature of the subject, which is very voluiuiiiotis, may be omitted here because a full account 

is given in Bull. No. 54, pp. 1 to 30. At the present stage of progress of the kinetic theory of gasea 

the air thermometer is still the only apparatus available for absolute high temperature measurement, 

anil all data are directly or indirectly derived from it. Au account of work of this kind ia also given 

in the bulletin.

*Cf. Phil. Mag., (5), vol. 29, 1890, pp. 141-157.

8 Groshans: Fogg. Ann., LXXYIII, p. 112,1849.
12 FUSION AND PRESSURE. [BULL. 103.

other suitable metal, and then in turn be further calibrated by means 

of its boiling point. This is about the idea. It is not wholly illusory, 

as I think the present paper, which in spite of its approximate character contains considerable work, will show.

2. The pyrometer. Let me say, too, that theplatinum/ platinuni-iridiuni 

thermocouple used had on a former occasion' been tested for polymerization anomalies by minute comparison with 

the porcelain air thermometer,2 and none were 

found. The alloy contained 20 per cent of iridium. M. Le Ohatelier3 unjustly rejects theplatinuin-iridiuni couple because of irregularities 

of the kind referred to. When the range of 

temperature is very large the Aveuarius-Tait 

equation is found insufficient; but this equation subserves a good purpose when interpolation between two fixed temperature data; 

lying anywhere on the scale, but not very far 

apart, is called for.

APPARATUS.

3-. Low boiling points. Boiling points be-' 

low 500° may be studied in a closed glass 

tube aa (PI. I), along the axis of which a thinwalled tube, del, open at both ends, passes 

quite through'. In the bottom of the annular 

space between the tubes the ebullition liquid, 

kit, is placed, and it is heated by the Gibbs' 

ring burner, rr. A funnel-shaped asbestos 

screen, nn, protects the upper tube against 

direct radiation. Oth er screen s an d j ackets, 

pp, are suitably added. The upper end of the 

tube, aa, communicates with the air pump 

through the tubulure h. Finally, a fj, the 

thermocouple to be calibrated, consisting of 

platinum and platinum-iridium wire, is inserted into the bottom of the central tube, dd, 

with the'junction o just above the plane of 

no. i.-Boiiing crucible for high the ebullition liquid, kk. The upper part of

temperatures. Scale, J. ^ ^^ ^ ^ ^^ ^^ asbestos wicking

(not shown), extending almost as far down as o.

The wires of the couple pass through parallel canals in a rod of fire 

clay, xy, and are thus well insulated. I may add that the boiling points

'Barus: Bull. U. S. Geol. Survey, No. 54, Chapter iv.

* Unfortunately circumstances did not permit mo, to make use of the former air thermometer comparisons, nor ,v<is it expedient to repeat the work.

3 Le Chatelier: Bull. Soc. Chimique Paris, Vol. 45, 1880, p. 482. Cf. Phil. Mag., (5) vol.34, 1892, 

p. 376.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. I

BOILING TUBE AND APPURTENANCES FOR LOW TEMPERATURES. SCALE f
BABT7B.] BOILING CRUCIBLE. 13

of mercury, sulphur, etc., for all pressures compatible with the strength 

of tube are conveniently obtained in this way. The vacuum boiling 

point of cadmium is also easily reached. Boiling may be kept up for 

any length of time.

4. High boiling points. For boiling points above 500° it is more convenient to use glazed porcelain or fireclay crucibles of the form efd^ 

bdc, (Fig. 1). The ebullition liquid is shown at Iclc, in Fig. 2, and fg is

FIG. 2. Furnace with crucible in place. Scale

the central tube in which the thermocouple, del, is to be introduced. To 

vary the pressure under which boiling takes place the tube a is connected with an air pump. Finally, a tight joint at ed is secured by 

calking with asbestos wi eking, and then filling up with fusible metal 

the annular space or trough left above the asbestos.

The crucible, e/rZ, is surrounded by a small furnace of Fletc,her's composition, FFF'F', Fig. 2, and heated with, one or more blast burners,
14 FUSION AND PRESSURE.

AB. If the flame impinges directly upon the cold crucible it is apt to 

break it; but such breakage may be quite prevented by surrounding 

the crucible with a conical shell of asbestos. Unfortunately, the crucibles can be used but once unless the metal is cautiously poured out 

before solidifying, an operation which does not always succeed for 

they are usually fractured by the solidifying metal, A;fc, on cooling. 

Nevertheless, the single experiment may be prolonged almost indefinitely; that is, for half a.day or more. I found no difficulty in 

obtaining vacua of two or three millimeters at extreme white heat. In 

this case the crucibles must be well glazed internally. § 13.

5. Torsion galvanometer. The best method of measurement is doubtless a null method,in which the thermoelectric constants are expressed 

in terms of a given Latimer Clark's cell. Eecalibrations are then rarely 

necessary. But the computation of observations occurring in great 

numbers is somewhat inconvenient. In this respect the torsion galvanometer offers decided advantages. A form of apparatus of this kind 

is shown in Plate II,-so that little further description will be necessary. A A is the coil of wire, and BB the astatic system seen in cross section. The system is suspended by aid of a fine platinum wire 13E; and 

inasmuch as AA is wrapped on a heavy frame of copper, the motion 

of the needle is aperiodic. Torsion is imparted by aid of an alidade 

DD, and the amount registered by a large circle graduated in degrees. 

Fractions of a degree are read off by a mirror and scale adjustment, 

the parts of which are (7, MM and $, T being the telescope.

The scale proper ss is on transparent glass, and S a white diffuse reflector, so that the scale may be more distinct.

The instrument is high enough to be manipulated by the observer 

standing. When the current passes, the deflected needle is twisted 

back to a fiducial position, parallel to the windings, and the amount at 

once read off. Then the current is reversed and a similar reading 

made. Since the resistance of the coil A A is practically the only resistance of the thermoelectric circuit, these deflections are directly 

proportional to the thermoelectroinotive force.

The two magnets BB' Plate II, Fig. 1 and 2, of the astatic system 

each consist of a battery of four flat magnets, about 10. centimeters 

long, and of glasshard steel, consecutively annealed at 100° both for 

temper and for magnetic permanence.1 A square frame of aluminium 

and hard rubber, embracing the upper half of the coil AA, connects 

the magnets. To this the adjustable mirror is attached. The torsion 

fiber is a platinum wire, .018 centimeter in diameter. It therefore has 

considerable strength to resist wear and tear. Finally, the plate-glass 

doors xyz, which close the magnet box, are easily removable, so that the 

magnet and mirror are conveniently accessible.

The instrument has two zeros: the optical zero of the mirrors, relative to which the reflected scale readings are symmetrical, and the

'Of. Bull. U. S. Geol. Survey No. 14, 1885, p. 171. Of. Chapter VI of the s^me bulletin.
U. 8. GEOLOGICAL SURVEY

BULLETIN NO. 103 PL. II

TORSION GALVANOMETER FOR TH ERMOELECTRIC PYROMETRY. SCALE
BARU8.] TORSION GALVANOMETER. 15

magnetic zero of the astatic system, relative to which the deflections 

are symmetrical. The two»fiducial marks should coincide. The magnetic zero is shown by the fact that. the mean of the scale readings on 

commutation coincide with the zero reading for no current. In case 

of a system of needles very nearly astatic, the optic zero may be determined by plotting scale readings in terms of twist registered by the 

alidade without current, and noting the position of symmetry in the 

circurnflexed curve of the chart.

6. It will be seen that by bringing the needle back to zero by twisting the fiber, the effect of the earth's local magnetic field is almost 

wholly eliminated in an adjusted instrument For let u be the effective magnetic moment of the system and I the intensity of the current, 

T the coefficient of torsion and y the twist necessary to bring the 

needle back to zero. Then, apart from unnecessary constants,

I u + r <p=0; -qt Iu / T. ................. .(I)

Again, in case of deflection </>' in a magnetic field of intensity H parallel to the coils,

I u cos v'+ry'+H u 1 siiif '=0.

Supposing the deflections very small,

p'=Itt/(T+ H U').......................... (2)

Now, iii an incidental adjustment I found ^=4-35; <p '=^-00. Hence,

r 400

In other words, the magnetic resistance is about one-tenth the torsional resistance to deflection by current. Now, inasmuch as deflections 

are used only to correct the torsion value, which is increased or decreased 

in single degrees, the effect of magnetic resistance is quite negligible. In 

measuring 100°, ?> =4.35, and the correction must be less than -6. Hence 

the magnetic resistance is less than -06, or less than 1-5 per cent off. 

But inasmuch as. the apparatus is primarily intended for temperatures 

greater than 350°, where <p >20°, it follows that the magnetic resistance 

is usually quite negligible. A little care in the magnetization of the 

needle will produce the astatic condition much more fully than was done 

in the above experiment. The same relations apply for finer fibers, 

where twists are larger.

A few examples ,of the deflection D for 100° at the hot junction, in 

case of a thick platinum fiber (diameter .0055 centimeter), and variety 

of different magnetic fields may be added.

Factor.

 893

3-45

3-08

3-402

D

7-235 

7-235

7-324 

7-319

7-290 

7 -270

7-440 

7-437 

7-434

Remarks.

>Strong field. Magnetic zero obtained by astasizing magnet.

S Astatic needle. Fiducial aero obtained by twisting.

£ Astatic needle. Coils in its plane.

(Astatic needle, kept in the plane of the coils by twisted 

( fiber.
16 FUSION AND PRESSURE.' [BULL. 103.

It follows finally that in the above instrument therinoelectromotive 

force-is expressed only in terms of the torsion of a platinum fiber, supposing-the needles to be so tempered and magnetized as not to change 

their magnetic permanence. Hence thernioelectromotive forces are not 

only expressed in terms of a fixed standard and therefore comparable 

with each other after the lapse of time, but the range of meastinnent is 

enormous. Any temperature between 100° and the intensest white heat 

may be measured without farther adjustment. These desiderata, added 

to the convenience of manipulation, and the strength of the instrument 

against wear and tear, constitute the advantages of the galvanometer 

described.

In the practical form of this apparatus the torsion circle need not be 

more than 6 inches in diameter, accurately divided into degrees. The 

alidade should be provided with a lens. A silk fiber suspension may 

be put in the case xy, so that the needle may at any time be unhitched 

from the platinum fiber, and attached to the silk fiber. A magnetic 

position of equilibrium parallel to the coils is thus easily obtained.

Inasmuch as both the internal resistance of the coils, the magnetic 

movement of the needles and the elasticity of the platinum fiber change 

with temperature, the torsion galvanometer has a notable temperature 

coefficient. .This, however, is determined at once by measuring the 

same temperature (hot junction) at two different temperatures of the 

galvanometer. The boiling point of mercury is a convenient datum for 

this purpose. Changes of temperature at the galvanometer are to be 

guarded against by placing a thermometer in the case.

7. Cold junction. From what has been stated, if D be the amount of 

torsion corresponding in a given instrument to the temperatures T and 

t of the junctions of the given thermocouple,

D=a (T t)+b(T2 t2 ) ......................(1)

Again if d=a (t 20)+& (t2 202)............................... (2)

D20= J)+d=a (T 20)+& (T2 202 )......... .(3)

Hence a small table corresponding to equation (2) is to be computed, 

from which the value of d for each value of t between 10° and 35° may 

be taken. A short preliminary calibration suffices for this purpose. 

In this way the observer may at once deduce D2ofroin D, where D2o is a 

function of T the temperature of the hot junction only.

By aid of the boiling points of water (100°), mercury (357°), sulphur 

(448°), cadmium (780°), zinc (930°), bismuth (1,500°), the quantity D20 

may then be graphically constructed as a function of T, and the points 

between consecutive boiling points filled in by equation similar to (1).

From a chart of this kind the temperature T, corresponding to any 

degree of twist D2n , may be taken with facility.

OBSERVATIONS.

5. Mercury. In the above apparatus the normal boiling point of 

'mercury is sharply determinate; but there is considerable difficulty in
BOILING POINTS, MERCURY. 17

determining tlie low-pressure boiling points. Unless the heat be regulated to a nicety the lower layers boil under the pressure of the upper 

layers. Again, since the agitation of the liquid nearly ceases in approximate vacuo, a flame of moderate intensity presupposed, the rate 

of evaporation is retarded in relatively greater degree. In the case of 

a liquid of smalt specific heat, films of which do not adhere readily to 

glass, it is therefore to be suspected that both liquid and vapor will be 

superheated. On the other hand, if the flame of the burner be intensified so as to produce violent ebullition at low pressures, the liquid can 

be superheated to such an extent that its direct radiation on the junction of the thermocouple may heat it as much as 10° above the boiling 

point.

Accordingly I was not surprised that the temperatures obtained in 

the static method by Kegnault, Hagen, Hertz, Kamsay and Young 1 

are as a rule below the corresponding boiling points of the present 

dynamic method. It is only by taking great pains-in the adjustment 

of burner and apparatus that my temperatures began to coincide with 

those of Kegnault. But this nice adjustment introduces arbitrary conditions; hence low pressure mercury boiling points are tobe rejected. At 

high pressures the unsatisfactory circumstances mentioned fall away; 

and the rate at which boiling point changes with pressure is enormously smaller.

In the following tables, 1 and 2,1 give instances of my results. The 

data of Table 1 were obtained at an earlier date, before I became aware 

of the grave difficulties encountered. T. is the boiling point for the 

pressure P, in centimeters of mercury:

TABLE 1. Boiling points of mercury (superheated)

P

cm. 44-2

37-5

17-5

1-0

0-7

0-5

13-3

24-4

T

°G.

330

325

290

195

190

170

279

304

P

cm. 5

6-4

12-0

25-2

47-0

76.2 2

T ,'/

°0.

194

256

280

310

330

356

199

P

cm.

0.3

0.3

0.1

T

°C.

198

184

183

In the following table are later results, obtained with great care, relative to the conditions stated at the outset of the present paragraph. 

The agreement with Kegnault's data is very much better, but the temperatures are still high, particularly in the region of low pressure (cf. 

Fig. 2). D20 , the twist corresponding to T, has been added, to show the

1 .Ramsay and Young; Join-. Chem. Soc.,vol. 49, p. 37, 1887; Landolt ami Boornstein's tables, p. 56, 

Berlin, Julius Springer, 188). I may advert in passing to a discussion between Messrs. Ramsay and 

Young and Kahlbaum. The former, corroborating Regnault's law, maintain that vapor tensions, 

whether obtained by static or dynamic mode of measurement, are identical. Kablbauin believes that 

he has found a dillerenoe. Cf. Boiblatter, vol. 1«, 1886, p. 485; ibid., vol. 11, 1887, pp. 88, 430.

Bull, lt'3 2
18 FUSION AND PRESSURE. [BULL. 103.

delicacy of the apparatus, PI. II, p. 14. Twist is expressed in degrees 

of arc: - * .

TABLE 2. Soiling points of mercury (superheated).

p

 1

 2

 2

2-6

2-7

2-7

4-5

4-6

12-6

12-5'

20-7

20-9

29-4

29-4

47-3

48-0

48-5

76-43

-DM

8-10

8-10

8-11

11-43 n-58

11-62

12-22

12-23

15-44

15-43

~ 16-90

16-95

17-75

17-74

19-58

19-65

19-75

21 -323

T

164

164

165

216

218

219

228

229

276

276

2117

298

308

308

334

335

336

357

P

 2

 3

 5

2-0

2-3

5-2

9-9

9-8

17-2

17-4

.31-5 31-8

50-3

50-5

76-43

-Da,

8-40

8 '28 8-49

10-84

11-25

12-93

14-98

14-87

16-24

16-23

18-07

18 -10

19-69

19-74

21 -484

T

168

166

170

208

214

239

270

268

288

288

313

314

335

335

358

9. Sulphur. The behavior of sulphur is peculiar. On removing tlie 

pressure to about lcm, the substance soon passes into the treacle state, 

and the fall ebullition observed under atmospheric and other pressures 

changes into a sticky frothing.

Exact temperature data can not, therefore, here be expected. The following table (3) is an example of the earlier results obtained:

TABLE 3. Soiling points of sulphur.

P

cm. o

 o

2-4

- T

°G.

218

205

263

P

cm. 4-8

7'0

11-2

T

°G.

298

316

337

P

cm. 21-2

39-8

76-0

T

°0.

374

410

448

The following table contains results of a later date, obtained by taking great care in guarding against superheating:

TABLE 4. Boiling points of sulphur.

P

55-36

55-41

ut KA .7£ iif

48-30

4758

37-59

37 -57

28-67

28-80

20-68

20-70

14-37

14-49

11-15

11-25 6-11

6-35

6-55

Ao

26-57

26-59

26-49

25-87

25-64

24-51

24-39

23-44

23-51

22-23

22-25

20-76

20-73

19-66

19-77

18-05

18-20

18-30

T

428

429

427

420

416

402

399

386

387

370

370

349.-

348

355

336

313

- 315

316

T 

Regnault.

429

429

428

422

421

407

407

393

394

376

376

358

359

346

347

321

323

324

P

4-06

30-69

30-70

13-01

12-93 5-61

5-91

614

3-2!> 3-44

 75

1-05

1-39

1-67

75-84

75-87

D20

16-80

23-65

23 -65

20-18

20-18

17-28

17-51

17-62

15-55

15-5]

10-76

11-33

11-85

11 -21

27 -976

 27-999

T

295

389

389

342

342

302

305

306

278

277

206

215

223

228

446

448

T 

Regnault.

305

396

396

354

354

317

320

321

295

297

252 *200

*266

*275

448

448

* Sulphur sticky.
BOILING POINTS, SULPHUR, ZINC, CADMIUM. 19

These results agree fairly well with those of the earlier table. I have 

added the values of T, exterpolated graphically from llegnault's data, 

by aid of the Dupre"-Bertrand equation. (Of. § 14.)

Log#==19-10740-46S4-49/0-3-40483 log 0, which holds between 

0=663 and 0 843 absolute degrees centigrade1 . It will be seen by 

comparison of iny values with the data predicted by this formula that 

it is much in error at low pressures. The divergence is largest in the 

neighborhood of llcm , and is here greater than 10°.

10. Zinc. The following table contains data of four sets of experiments for zinc. The first of these were made in the glass tube (Fig. 1) 

at low pressures. Although in this case there was considerable volatilization, I did not observe any ebullition. In the table, the result marked 

* is the only datum of this work inserted. Change of temperature with 

pressure was not very obvious.

The remaining data of this part of the table are legitimate. The 

criterion of a boiling point is change of temperature with pressure. In 

the second and third parts of the table I aimed at greater accuracy. 

Each of the values given is a mean of two or three distinct measurements; t refers to a low position, | to a high position of the thermocouple 

in the central tube (see Fig. 2).

TABLE 5. Boiling points of zinc.

p

cm. 1-0

4-0

' 6-5

9-6

10-1

15-0

27-1. 34-5

42-5

53 '5 70-4

T

°G

*582

710

732

757

772

785

837

857

873

897

933

P

cm. 4-2

3-5

2 '8

C-2

9-9

10-6

26-4

36-8

47-7

55-7

65-3

77-3

77-3

T

°C

710

099

684

730

758

802

838

803

884

900

914

1928

J922'

P

cm. 2-6

C-7

15-8

20 -4

37 '5 47-3

57-0

05-4

77-1

T

°0

075

731

792

833

804

884

904

916

933

11. Cadmium. The first part of Table 6 contains results obtained 

in a glass tube. Ebullition in vacuum was obvious. But inasmuch as 

the limit of the power of the ring burner was not much above 500°, 

the remaining thermal data are too low.

The experiments of the second and third parts of this table were 

made in the porcelain crucible. They are legitimate, change of temperature taking place with every change of pressure. I was unable to 

make the crucible satisfactorily tight, so that mean values of fluctuating pressure had to be made use of. Again .cadmium is more easily 

superheated than zinc;.so that the present temperatures are probably 

high.

'I computed the inferior prolongation of the curve and plotted the results. From the chart the 

values of T were taken to a high degree of accuracy.
20 FUSION AND PRESSURE. [BULL. 103.

A repetition of the experiment failed in consequence of breakage of 

the crucible. It is interesting to note here that if zinc boils at 930°, 

cadmium will boil at a temperature not much below 780°.

TABLE 6. Boiling points of cadmium.

P

cm. 00

2-75

5-25

7-70

T

°C.

444

526

549

5C2

P

cm. 2-2

2-5

2-6

3-2

7-5

10-5

15-7

18-9

26-2

29-2

35-5

38-1

48'9

51-7

62-4

64-4

65-6

75 '6 75-0

75-6

T

p c.

549

552

565

574

620

639

667

681

702

706

724

729

745

750

760

766

766

772

770

774

P

cm. ' 6-3

8-4

22-6

27-4

34-2

51-0

56-3

63-6

65-6

75-5

75-5

75-5

T .

°C.

.606

622

686

704

722

752

760

770

772

786

788

781.

12. Bismuth. Table 7 contains results for bismuth. In the first part 

of the table temperature does not change with pressure, hence a boiling point is not reached, in the second part of the table temperature 

certainly oscillates with pressure, hence the temperature corresponding to the lower values of pressure (3 to 4 cm.) are boiling points. 

The temperatures corresponding to the higher values of pressure (9 to 

10 cm.) are below the corresponding boiling points, for I found that on 

further increasing pressure, the temperature did not increase. These 

temperatures are therefore at the limit of the heating power of tlie 

furnace. At least five minutes must be allowed for each observation. 

The top of the crucible, moreover, should be filled with asbestos, to 

diminish loss of heat by radiation.

TABLE 7. Hoiliny points of bismuth.

P.

cm. 2-6

5-8

2-6

8-1

8-8

2-7

9-8

2-4

T.

°G.

1152

1164

1165

1182

1186

1183

1194

1186

P.

mn. 3-2

8-6

9-7

3-2

3-7

4-2

8-7

3-9

3-4

9-5

3-4

4-0

9-7

3-4

3-9

9 (> 3-I1

4-2

T.

°G.

1199

1211

1207

1206

1222

1215

1247

1213

1204

1236

1207

1217

1260

1206

1221

1258

1215

12:j:i

Remarks.

Elainc intensified. R. P. criterion satisfied.

.Limit of the heating power of the burner.
BABUS.] VAPOR TENSION EQUATIONS. 21

13. Remarks. In the above tables, 1 to 7, the criterion of boiling point 

has therefore been change of temperature with pressure. When this 

was not observed, the data were rejected. The method of obtaining 

low boiling points from the liquid is doubtless objectionable, because 

of the liability to superheating. In special measurements made with 

zinc, 1 however, I found that the error thus introduced is negligible. 

There seems to be less superheating in case of metals and high temperatures, supposing the temperature of the environment to be reasonably 

near the boiling point (100° or 200° above it). In case of bismuth and 

metals of higher boiling points, the difficulties of experiment are such 

that I do not think a low pressure vapor bath is feasible.

In regard to the crucible used, I may remark that experimentation 

will be much facilitated by using tubular forms made in a single piece. 

In this case the trouble experienced in calking the joint of Figure 1 

will be obviated. The metal, previously granulated, may easily be introduced through the tubed In this case I have no doubt that very 

high vacua at white heat will be attainable. It is advisable, moreover, 

when very high temperatures are to be reached, to place the crucible 

and lid wholly within the furnace, allowing only a narrow tube to project out of it

INFERENCES.

14. Available equations. Equations for expressing vapor tension in 

terms of temperature have been invented in great number, and among 

them the simple form of Magnus and the more elaborate exponential 

devised by Biot and used by Eeguault are given in most text books. 

A remarkably close fitting exponential is investigated and tested by 

Bertraud.a Quite recently M. Ch. Antoine 3 has proposed and a.pplied a 

new form. Following the early suggestions of Bertram! 4 and of J. J. 

Thomson, 5 1 have used the equation of Dupr6,6

log p=A B I 6 G log e. ...... ...;....... (1)

inasmuch as J. J. Thomson has given it an independent interpretation. 

The meaning of the equation is clearer in the differential form :

dp / cl B= p (CJ 6 B I 8 2 ) ................ .(2)

or .

6* */ #

--_... ............ ....(3)

with reference to which it is to be observed that C / B is a small quantity (about 1/1000).

1 Bull. U. S. Geol. Survey, No. 54, p, 109.

2 Bertrand: Thermo dynamique, pp. 154 to 162, Paris, Gautliier-Villara. 1887.

3 Ch. Antoino: 'C. K., CVH, p. 681, 1888; ibid., pp. 778, 836, 1888.

 < Bertraml : loc. cit. p. 90 to 102.

8 J. J. Thomson : Applications of dynamics, etc., p. 158, Maciuillan, 1888.

6 Dupr6: Tli6orie mecaiiiqne do la chaleur, pp. 96 to 110, Paris, (.Tautliiers-'V'illars, 1869.
FUSION AND PRESSURE. '[BOLL. 103.

15. Constants computed. Applying equation (1) to the results of the 

tables 1 to 7,1 found the following set of values by direct computation:

TABLE 8. Constants. A, B, C, variable.

Metal. A

+ 3-583

OK.QCQ

30-567

+42-265

+24-774

B

+3084

366-1

+ 1391

+11435

+13495

. C

 1-1371

13-066

-11-180

+10-022

+ 4-763

These results are grossly irregular, even as to sig*n. This might have 

been expected. To get comparable values for constants the observations in case of complex equations must either be very fine or in great 

number; Other direct methods gave similarly irregular constants, 

which need not be entered here. Nothing can be learned from them.

Bearing in mind, therefore, that it is my object to detect possible 

relations, and that my high-temperature boiling points, are necessarily 

somewhat crude, I will facilitate preliminary computation by observing 

that iu Dupre"'s data the prevailing value of A is nearly 20. Putting 

A=20 the following set of constants were obtained, in which, of course, 

there is greater degree of uniformity, Water has been added from 

Dupre":

TABLE 9. Constants. B and C, variable.

Substance.

"WotAr

A

Of V 3 94.

Ofi

20

20

20

20

If

97Q1

4345

4379

7467

8433

12561

G

^ flfift

4-013

4-217

3-603

3-456

The results of this table are encouraging. From an inspection of 

the constants I was led to suspect better agreement in making C constant and A variable. This step is further suggested by assuming, 

conformably with the indications of table 9, that for any two substances, 8 and $', the boiling points, 0 and .0', corresponding to a given 

pressure,^, will follow the relation B / B'=o I o'=.n, where n is constant 

for the given pair of substances. This virtually postulates a fundamental equation of the form (1) from which all others are derived by 

substitution, as follows:

logp=A-B/e-C log<9.....................(1)

=A nB/n9- ClognO+G log n 

=A'-B'/0'-Clog0'.. ................(4)

The constants of Table 10 are obtained by supposing C to be constant 

for all the substances. As to the choice of a value, I noticed that the 

mean C of Table 9 is almost identical with Dupre's C for water. Hence 

it was chosen.
BARUS.] BOILING POINT CHART.

TABLE 10. Constants A and B, variable.

23

A

19 -029

19 -776

20'03

20 -98

21 -51

JS

2795

4390

4458

7443

8619

12862

0

3-868

3 '868

3-868

3-868

3-868

3-868

The constants might be much improved by successive trials; but further work would be wasted.

16. Graphic representation. In order to clearly exhibit the point of 

view I have taken, it will be necessary to plot these results graphically. 

This is done in Plate III, in which the absciss® are pressures in centimetres of mercury and the ordinates boiling points in degrees centigrade.

The curves passed through the observations are computed for the 

constants of Table 8. Some points computed by Table 9 are marked; 

points computed by Table 10 are also marked. The agreement of observed and computed results is quite within the errors of observation, 

as will at once be evident from an inspection of the chart. In case of 

mercury I have added the vapor tension results of Regnault, showing 

that they are uniformly lower than the present data. The reasons have 

already been given in § 8.

The results for bismuth are particularly interesting. Unfortunately 

it was impossible for me to calk the crucible tight enough, in. order 

that the low-pressure boiling point of bismuth might overlap the normal boiling point of zinc, which limits the calibration interval of the 

thermo-couple. The chart shows that the interval of extrapolation is 

about 270°. This makes the bismuth results less certain. For this 

reason, perhaps, the normal boiling point of bismuth, as deduced by 

Groshaus's principle is too high, being 1550°. Carnelley and Williams,1 

using a caloriinetric method, obtained only 1450° as their maximum 

value. It is probable, however, that the radiation errors in Carnelley 

and Williams's experiments would tend to make their data too low; 

nor have they any sure criterion that ebullition had actually set in. 

In experiments of my own,2 using a Fl etcher furnace with three blast 

burners, I signally failed to boil bismuth in a number of trials. The 

boiling-point criterion in the present results is beautifully exhibited: 

When pressure increases the group of points B on the chart pass into 

the group of points .A; hence the group B are boiling points. When 

pressure increases further the group A does not increase in temperature; hence group A are not boiling points, but merely indicate the 

maximum heating power of the furnace.

17. Conclusion. I am perfectly aware that the method pursued 

above, in endeavoring to reach perspicuous results, is forced. Ber1 Ciirnelloy and Williams, Journ. Chcra. Soc., London, vol. 35, 1879, p. 565. 

» Bull. U. S. G. S., No. 54, pp. 11C-118,124.
24 FUSION AND PRESSURE. [BOLL. ion.

trand computes the constants of Dupr6's formula for 16 substances, and 

shows its admirable agreement witli the observed data throughout. 

But the constants in such a case vary largely: A between 4 and 21 

(pressures being expressed in centimeters of mercury); G between 9 

and + 5. In any- such grouping of constants as I have attempted, the 

agreement of the formula would therefore be lost. It is worthy of remark, however, that in 10 out of the 16 sitbstances A lies between 15 

and 21-5, and in one-half of the substances C lies between 3-2 and 4-2.

When, however,- the errors left in any attempt to group the constants are considered, not so much with reference to the small range of 

temperatures of a single substance, but rather with regard to the relatively enormous range of temperatures exhibited by these phenomena 

as a whole, and by a diagram, such as PI. Ill, for instance, then the errors in question assume much smaller importance. In the above pages 

I have presumed to believe that at the outset the wide temperature 

comparison is the one which ought first to be made, and some fundamental relation applicable to the whole range of temperature investigated. After this has been done, the said relation may then be modified 

to suit the individual and exceptional case.

I can state this more clearly as follows: Gposhans's derivation of his 

principle is sufficiently simple; for, if vapors have identical coefficients 

of expansion, 1/273, say, and their densities be expressed relatively to 

the density at the normal boiling point in each case, then the ratio 

of absolute boiling temperatures corresponding to any two given pressures will be the same for all vapors. This inference is incorrect just 

in proportion as the application made of the Boyle-Charles law is 

incorrect.

However, Dupre in deriving his formula makes virtually the same 

assumption.1 Again, J. J. Thomson 2 introduces Boyle's law into the 

mean value of the Lagrangian function investigated for the present 

phenomena. Inasmuch, however, as the forms of two arbitrary functions have here to be determined by experiment, the insertion of Boyle's 

law suffices Thomson's purposes.' Following the model of his work, I 

hoped to find some suggestion as to the modification of Dupre's equation, such that it may be the outcome of an original type for all substances, by inserting Van derWaals's law,^=^@/('y &) a/fl2, instead 

of Boyle's law into the proper term. It seemed plausible that .Dupr6's 

equation could thus be corrected by aid of constants, the molecular 

interpretation of which has already been given by Van .der Waals. 

Performing the operations, I find, rigorously,

where a and & are Van der Waals's constants. This equation, though 

capable of simplification, essentially involves C, and is therefore not 

suggestive; i

'Bertrand: loc. cit., p. 101. ' 'Thomson: loc. cit., p. 158.
U. 8. GEOLOGICAL SURVEY BULLETIN NO. 103 PL.

I500

I400

I300

iaoo

1100

40 50 60 70 80 90
OHAPTEE II.

. THE CONTRACTION OF MOLTEN IGNEOUS ROCK ON PASSING 

FROM LIQUID TO SOLID. '

INTRODUCTORY.

18. The rock. The following volume measurements were made for 

Mr. Clarence King, on a sample of diabase which he furnished. The 

object thus far is to develop the general character of the expansion 

phenomenon, and for this reason a fusible rock, without action on hot 

platinum, was selected. In future researches, graded rock magmas, 

passing from extreme acid to extreme basic, will be operated on.

19. Literature. The importance of the question is well known, but a 

literary discussion .is superfluous here, sin.ce Prof. F. Mess 1 , of Hohenheiin, not long ago made a careful survey of all that has been done on 

the subject. The reader desiring specific information is referred to this 

interesting pamphlet. " Es ist em durch Ooutraste buntes Bild," says 

Prof. Niess (loc. cit., p.36)," welches in dervorstehenden Oitatenlese dem 

Leser zu entrollen war, und aus dem Wirrwarr entgegengesetzter Ansichten heben sich nur zwei Korper: Wismuth und Eisen,heraus, liber 

welche man wohl mit absoluter Sicherheit die Acten als geschlossen 

bezeiehuen kann, und zwar in dem Sinue, dass fur sie die Ausdehnung 

im Momente der Verfertigung als zweifellos bewiesen gelten kann. Die 

iibrigen Metalle stehen noch im Streit,und fiir sie gilt das Grleiche was 

wir fiir die kiinstlichen Silicate zu fordern hattcn * * *" Now, iron, 

in virtue of the occurrence of recalescence (Gore, Barrett), is scarcely a 

fair substance to operate upon, and it heightens the confusion to find 

that Prof. Niess, after carefully weighing all the evidence in hand, is 

obliged to conclude that rocks expand on solidifying.

The present experiments show beyond question, I think, that at least 

for diabase this is not true. I find that this rock not only contracts 

between 3.5 to 4 per cent on solidifying, but that such solidification is 

Sharp and only apparently continuous, and that the fusion behavior 

throughout is quite normal in character. Hence with certain precautions which I shall specify in the course of this paper, §21, the 

volume thermodynamic relations which I deduced by acting on organic 

bodies may be applied to rock magmas.

20. Effect of fusion (polymcrism). The, rock after fusion is changed 

to a compact black obsidian and quite loses its characteristic structure.

'Niess: " Ueber das Verlialten dor Silicate, etc.;" Programm zur 70. Jahresfeior d. k. Wiirtemb. 

lundw. Academie. Stuttgart, E. Koch, 1889.

25
26 FUSION AND PEESSUEE. [BULL. 103.

It was therefore important to examine the volume relations of this 

change preliminarily. This is done in Table 11, where the densities 

obtained with lumps of the rock (mass M), at the temperature tf, are 

given, A being- the density before, A 1 after, fusion.

TABLE 11. Density, d, of the diabase, he/ore and after fusion.

ground).

A. BEFORE FUSION.

Massive pieces (not

Sample

No.

I

II

III

IV

nr

22 '8950

45 -3654

54-7208

69 -4940

t .

°0 

25

21

21

21

D d

3 '0161

3 -nisi

3 -0136

3 -0235

A A'

A

B. AFTEll FUSION.

I

II

III

60 -9330

33 -7059

29 -9777

21

19

19

3 -5013

3 -5496

-11 -1G8G

11 -2712

21 -021

(21 -00)

2 -7447

2 -7045

 090

 103

( Fused in clay cruci-

( out when cold. '

( Fused in a plati- 

\ num crucible.

The rock was fused both in clay and in platinum crucibles. In the 

latter case the density d of the known mass m of the platinum crucible 

had been previously determined, and D denotes the observed density 

of molten rock and crucible together after fusion. In the case where a 

clay crucible was used, this was broken away from the glass within 

and the density of the solid lump (glass) then measured directly.

A few small air bubble cavities were visible on the fresh fractured 

surface of the glass, due, I presume, to the possibility that most rocks, 

like most organic liquids, hold gases in solution, which separate on 

solidification. At some other time I will make sharp vacuum measurements of the density of ground powders both of the rock and of the 

glass, but I do not believe the results of Table 1 will be seriously 

changed by such a test.

From Table 1 it appears that the mean density of the original rock is 

3-0178. That of the glass after fusion is 2-717, showing that the result 

of fusion has been a volume increment of 10 per cent. This remarkable 

behavior is not new nor isolated. Mess (1. c., p. 47), quoting from Zirkel's Lehrbuch, shows even more remarkable volume changes of the 

same nature in garnet, grossularite, vesuvianite, adularite, orthoclase, 

augite; but I doubt whether the great importance of this behavior has 

been sufficiently emphasized. Suffice it to indicate here that it makes 

an enormous difference into what product the magma is to be conceived 

as being solidified, and that throughout this paper the molten rock solidifies into an obsidian. I am really only determining, therefore, those
X

BARUS.] TEMPERATURE MEASUREMENT. 27

volume changes which lie at the margin, as it were, of the more profound but chemically structural volume change, which latter may be 

reasonably conceived as producible by pressure alone under conditions 

of nearly stationary (high) temperature.

I may add in passing that, from the magnitude of the chemical change, 

I shall carry my work on the effect of pressure on chemical equilibrium 

of solids and liquids and on the solution behavior "solid-liquid" into 

greater detail than I have hitherto attempted.1

APPARATUS.

21. Temperature measurement. In work of this kind, an apparatus 

for the accurate measurement of high temperatures is the fundamental 

consideration. I may, however, dismiss this subject briefly here, since 

I discussed it elaborately in Bulletin No. 54, U. S. Geological Survey. 

The temperature measurements of this paper were made with thermocouples, of platinum and platinum with 20 per cent of iridium, and they 

had been frequently calibrated by aid of the porcelain air thermometer 

within an interval of 1100^ and tested for freedom from anomalies beyond that interval. Reference to the bulletin cited will show how 

thoroughly reliable this thermocouple is. Inasmuch as the process 

consists in expressing thermoelectric force by aid of a zero method in 

terms of a given Latimer Clark cell, the temperature apparatus is ot 

the same order of constancy as to time as the standard cell.

In order to find, however, how far this work was trustworthy after 

a lapse of more than four years since it was done, I made fresh check 

measurements of the boiling points of mercury and of zinc. The latter 

need only be cited here. My original datum of the boiling point of zinc 

expressed as thermoelectric force for the couples under consideration 

was e-2o = 11,074. micro volts, the cold junction being at 20° C. The new 

experiments referred to gave me data as follows:

Microvolts. 

Thermocouple No. 35 ................................................. e.M = 11,168

No. 36 ................................................. =11,127

No. 39 ................................................. =11,116

No. 40 ................................................ = 11,136

Mean .......................................................... =11,137

agreeing very closely with two subsequent, specially careful measurements, viz:

Microvolts. 

No. 36................................................................ ei0 = H,131

No. 39................................................................ = 11,134

Thus the difference of values new and old is only CO microvolts about 

£ per cent as regards electromotive force, corresponding to something over 4° at 1000°. In view of the excessive use and abuse to

1 Am. Journal, vol. 37, p. 339, 1889; ibid., vol. 38, p. 408, 1889; ibid., vol. 40, p. 219, 1890; ibid., vol. 

41, p. 110, 1891; ibid., vol. 42, p. 40 ct 8eq., 1891; Phil. Mag., (5), vol. 31. p. 9, 1891.
28 FUSION AND PRESSURE. [BULL. 103.

which the couples had been put in the meantime, this result is in itself 

gratifying.

Endeavoring to find, however, where this discrepancy was to be 

sought, I also made fresh comparisons between the Latimer Clark 

standard and a normal Daniell of my own (bulletin cited, p. 100), in 

which the two cells are separate and only joined (with zinc sulphate 

solution) during the time of use. Supposing the Latimer Clark cell to 

have remained constant the succession of following values was found:

March, 1886, 20° C., L. C., e = 1 -435 Daniell, e = 1 -138

August, 1887,28° C., 1-435 . 1-139

September, 1891. 27° C., 1 -435 ' 1 -147

If, therefore, instead of regarding the L. C. cell constant, I had assumed the Dauiell as constant 1 , the thermoelectric difference for the 

interval of four years would be wiped out. Now my L. C. cells were 

made by me in 1883, when less was known about the subject than is now 

available 3 . I conclude therefore that the discrepancy is very probably in the standard cell employed and that my thermocouples have 

remained absolutely constant. *

Apart from this, the new standardization by aid of the boiling point 

of zinc fixes the scale irrespective of surmises or hypotheses, assuming that zinc boils at 930°.

22. General disposition of apparatus. This is given in PI. IV, on a 

scale of £, where figures 1 and 3 form a sectional elevation showing the 

parts chiefly with reference to their vertical height, and figure 2 a sectional plan in which the parts are represented with reference to the 

horizontal.

The molten rock ZZ contained in a long cylindrical platinum tube, 

largely surrounded by a tube of fire clay, FF, is fixed vertically in a 

long cylindrical furnace, .7X7) LL. The heat is furnished by six burners, 

J3J5, fed by gas and an air blast laden, if need be, with oxygen. These 

burners are placed at equal intervals along the vertical, three on one side 

and three on the other (PL IY, Fig. 2), and set like a force couple so 

as to surround the platinum tube with a whirlwind of flame. Suitable 

holes are cut in the walls of the furnace for symmetrical insertion of 

the insulated thermocouples, 51, and also at $, for fixing the sight tubes, 

.A, near the top and the bottom of the furnace. Parts of the envelopes 

of the platinum tube are cut away, so that its upper and lower end can 

be seen in the telescope of an external cathetometer. Thus the expansion of the platinum tube is measured directly. A vertical micrometer, 

Kkd, PL IV, Figs. 3 and 4, insulated so as to admit of electrical indications of contact, furnishes a means of tracing the apparent expansion 

of the rock ZZ.

In principle the operations are so to be conducted that under the 

conditions of slow cooling the magma may be relatively much less

1 Our laboratory affords no means for the direct measurement of electromotive force.

2 See Lord Ragleigh in Phil. Trans., June, 1884. and Jan., 1880; also Carhart, Am. J. Sci., Nov., 1884.
HAKUS.] VOLUMETRIC APPARATUS. 29

viscous than the practically rigid platinum envelope throughout the 

work.

The furnace stands on a massive iron base perforated with eight holes, 

into which vertical iron uprights are screwed, symmetrically surrounding 

the furnace and at a distance of 4 or 5 centimeters from its circumference. 

Only one of these is indicated, in part, at QQ, in PI. IV, Fig. 3, the 

rest with other subsidiary parts being omitted to avoid confusing the 

figure. Two of these uprights hold the vertical micrometer, two others 

hold the burners in place. To the fifth the sight tubes are adjustably 

attached, to the sixth the thermocouple insulators are clamped exteriorly to the furnace, and the remaining two fix the clay holders J5", JET", 

by which the tube FF is adjusted vertically. All of these uprights are 

hollow, and a current of water contirmally circulates through them with 

sufficient rapidity to issue finally still cold to the touch. In this way 

the observer "is able to move and change the accessories of the furnace 

with comfort even when the temperature within is maintained at 1500°. 

A single stream of water is sufficient, the ends of the uprights being 

joined by rubber tubing, and this same current additionally flows 

through the screen XX of the vertical micrometer and the high vertical 

screen of the cathetometer.

23. The furnace, It should be added to the remarks made in the pre: 

ceding paragraph that all the burners J3, j5, PI. IV, are fed by the same 

amount of gas and air by properly branching the large supply tubes. A 

graduated stop cock is at hand for regulating the supply of gas to a 

.nicety, whereas the air blast need not be regulated. Hence the furnace 

is fed with a mixture of gas and air, and temperatures from 1600° to 400° 

may be obtained by simply making the influx richer or poorer in illuminating gas. Burner constructions suitable for this purpose are given 

in Bulletin 'No. 54, p. 182. For higher temperatures the blast may bo 

made richer in oxygen, but I have thus far had no need of doing this.

The products of combustion are carried off by the two oblique tubes 

J57, jE7, in the lid LL. Note that the 'water screen bends around the vertical micrometer in such a way that flames issuing from E can do no 

injury. The central narrow hole in the lid L, through which the end 

piece eld of the .micrometer passes, is closed by a free plate of fire clay 

mm perforated so as to surround eld loosely.

The blast was furnished by a pair of large-sized Fletcher belloAvs, 

each with three sheets of rubber above the reservoir. These bellows were 

set so as to form a double-acting pump, and actuated by aid of a short 

crank on the axle of a small gas engine. The blast pressure so obtained is considerable, a requisite in the above instances. It can be 

regulated by lengthening or shortening the crank, Avhereby the arc 

of reciprocal motion of the bellows is increased, the frequency remaining unaltered. The efflux pipes of both bellows discharge into a common g:u; pipe leading to the furnace.

In order to obtain greater constancy of temperature and increase the 

high temperature efficiency of the furnace at the same time, it is es-
30 FUSION AND PRESSURE. [BULL. 103.

sential to jacket the furnace, _Z)D, and lid, LL, externally with a coating' 

of asbestos fully £ inch or more thick. I noted that in these cases the 

clay parts of the furnace became red hot throughout, Avhereas the uncovered furnace is not much above 400° externally. This indicates a 

smaller loss by radiation in the former case.

24. Fusion tube. The platinum tube holding the molten rock, ZZ, 

PI. IV, was 25 centimeters long and 1-5 centimeters in diameter, with 

walls about -02 centimeter thick. It .was drawn as accurately cylindrical as possible, and the bottom was plane and at right angles to the axis. 

To protect this tube from gases and to keep it from bulging in consequence of the pressure of rock within, the platinum tube is surrounded 

by a fire-clay tube, PI. IV, FF, Figs. 1 and 6, fitting loosely. Care must 

be taken to allow for shrinkage. Thus a fresh clay tube, after about two 

hours heating at 1500° shrank from a length of 25-4 centimeters to 24-6 

centimeters, i. e., -8 centimeter or more than 3 per cent. This shrinkage 

is permanent and uniform in all directions, and is not, therefore, due 

to viscous sagging5 after its full value has been reached, moreover, it 

ceases and the tube expansion is then normal. If properly sustained 

in the furnace the clay tube FF does not bend or warp. The holders, 

which I found very serviceable for this purpose, are shown at If, H, in 

PI. IV,- Figs. 1, 2, and 7. They are made of fire clay and held in position by suitable clamps on the outside of the furnace (not shown). In 

this way the fusion tube is to some extent adjustable.

The bottom of the tube, FF, is additionally fixed by aid of a perforated fire-clay ring, 0(7, Figs. 1 and 5, which embraces both the tube, FF, 

and a projection in the furnace, G.

25. Thermocouples. These are three in number and inserted through 

the walls of the furnace, DD, Plate IV, in the positions given at T, in 

Figures 1 and 2. But Figs. G and 8 give a fuller account of the adjustment. The tube, FF, is laterally perforated with three pairs of fine holes, 

t, tj tj corresponding to the two canals in the insulator, TT. The wires 

of the thermocouple are then threaded through t, and the insulator in 

such a way that the junction lies in a small cavity at t, immediately in 

contact with the platinum fusion tube. A hole is cut in the tube, FF, 

opposite t (see PI. IV, Fig. 8) and a similar one in the opposite wall of the 

furnace to facilitate these operations, the platinum tube being for the 

time removed. The advantage gained in this way is two-fold, since in 

the first place no part of the wires of the couple are directly surrounded 

with flame, and there is no danger of an accidental contact of these 

wires on the outsidaof the tube, FF. It is known that in the presence of carbon there is danger of passing silicon into the platinum, 

making the metal relatively fusible. Now, even if the hot gases of the 

furnace are reducing, they are to some extent stagnant in the insulating 

tubes, whereas in the flame they are constantly renewed. This I attribute to the protecting effect of the insulators.

The cold junctions of the thermocouples terminate in three pairs of 

mercury troughs, irfsulated by hard rubber, and submerged in a bath of
U. 8. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. IV

Thermocouple

Thermoc ouvle

Fig. 6

FURNACE FOR MEASURING VOLUME CONTRACTION OF MOLTEN ROCK. SCALE \.
DABU8.] VOLUMETRIC APPARATUS. 31

petroleum. With these troughs the terminals of the zero method, § 21, 

are connected at pleasure, so that the temperatures at the top, middle, 

and bottom of the fusion tube are easily determined. .Data are given 

in full below.

26. Sight tubes. It has been stated, v§ 22, that the increase of length 

of the platinum fusion tube, ZZ, is to be measured directly. For this 

purpose Grunow's excellent cathetometer is placed on a suitable pier on « 

the outside of the furnace, so that the prism of the instrument is only 

about 50 centimetres off from the platinum tube. To obviate the hurtful effect of radiation, however, a tall, flat water screen, 30 centimetres 

broad, 70 centimetres long, and 1 centimetres thick, and movable on a 

slide, is placed between furnace and cathetometer. Slots closed by 

plate glass are cut through the screen to correspond to the two positions of the telescope, and the furnace walls, DD, are similarly perforated, at $, above and below (see PI. IV, Figs. 1 and 2), so that the ends 

of the platinum tube may be seen. The top of the latter projects above 

FF; but this tube and the ring, CC, are perforated at 0, as shown in 

Figs. 1,5, and 6. When the furnace is red hot within, the end planes or 

lines stand out very sharply against the red-hot clay background, in 

consequence of a difference in the emissive power of the metal and the 

clay, and hence the measurement is possible with the necessary degree 

of accuracy.

It is essential, ho\vever, to prevent the escape of flame and gas at 8, 

and this may be done by closing these holes with sight tubes (only 

one of which is shown, A) of porcelain and about 15 centimeters long. 

The outer end of these is ground off square and a plate of plate glass, 

&, held against it by aid of the clamping device, aa. Surrounding 

the porcelain tube, J., with a layer of asbestos, and cutting a thread on 

the inner face of the brass ring, a, the latter may be screwed on to the 

soft asbestos, and then serve to secure an iron ring by aid of two machine screws, as shown. The iron ring holds the glass plate, &, in 

place. This joint should be well made, for if there is an escape of hot 

gases here, the glass is apt to break, though I have had no serious 

accident of this kind. At first, drops of water collect on &, but they 

disappear as the temperature rises.

27. Vertical micrometer. Figs. 3 and 4, PI. IY, give a full account of 

this instrument, both of which are sectional elevations at right angles 

to each other. A good millimeter screw, Klc, plays easily through the 

massive block of brass, PP, and the fixed lock nut, gg, and I is the vertical millimeter scale whereby the motion of the graduated head is 

registered. The block, PP, is bolted down to the thick bridge of brass, 

NN: by means of the screws JK, R, and the counter plate UU. The 

ends of NN are provided with sleeves, pp, and a clamp screw M, so 

that the whole micrometer may slide up or down, or be clamped in any 

vertical position on the uprights, one of which is indicated at QQ.

It has been stated that the registration of the micrometer is to be 

electric, and hence the screw, Kk, must be insulated. This is done by
'62 FUSION AND PRESSURE. [BULL. 103.

surrounding the screws J£, J$J, Avith a layer «; n, of liarcl rubber, from 

Avhich the ends alone project, and insulating the plate, PP, and the 

counter plate of brass UU, by interposed sheets of hard rubber })', n, 

and the washers </, g.

In order to provide for a certain amount of horizontal adjustment of 

the micrometer, sufficiently wide slots are cut in the brass bridge NN, 

("See figures) whereby the plate, PP, may be shifted about 1 centimetre 

in any direction and then clamped in position.

In Anew of the heat which continually rises from the furnace, a Vshaped screen, XX, through which water rapidly circulates, nearly envelopes the micrometer below. Water enters and issues through tubes 

V and Y at diagonally opposite corners of the top of XX. Inasmuch 

as the micrometer screw, JO;; passes through a narrow hole in the bottom of XX, this screen must also be capable of lateral adjustment, and 

this is easily accomplished by aid of two vertical screw hangers /<-, 7t, 

soldered to XX below and passing through wide slots in NN, to which 

they are secured in any horizontal or vertical position by suitably 

flanged nuts above and below NN. Thus it is seen that the micrometer and its water-screen slide as a single piece along the upright QQ, 

an arrangement which greatly facilitates the final adjustment. Q and Y are connected by a sufficient length of rubber tube, as is merely indicated in the figure. There is a like connection on the other side.

Finally, the end of JOc is prolonged by a straight cylindrical tube of 

platinum dd, which may be fixed to the steel rod Jc by aid of the clamp 

e in any position along the vertical. This tube dd fits the rod fc 

snugly, and should it become bent or warped by accidents, a special 

steel rod is provided by means of which it may easily be straightened 

again.

The lower end of d is clearly visible in the telescope of the cathetometer through the sight tube A. On being screwed down it enters the 

fusion tube ZZ axially, supposing the micrometer and fusion tube to 

have been properly fixed in position. In how far this has been done 

can always be seen by temporarily removing one of the efflux pipes E, 

PI. IV, Fig. 4, when the end of the fusion tube and the motion at the lower 

end of d is visible to the eye. On actuating the micrometer head of 

JO;, the lower end of d should show but slight lateral motion in the 

telescope. Usually the tube d becomes coated Avith an enamel of 

molten rock, but this is of no consequence, since the increase of length 

is noted in the measurements.

28. Telephonic registration. Since it is the object to find how far the 

meniscus of molten rock ZZ, PI. IV, lies below the plane of the top of 

the fusion tube, the moment of contact of ZZ and d is best registered 

electrically. So long as the interior of the furnace is red hot, the rock 

is a good electric conductor. Hence, if a current be passed into the 

screw Ii7<;, at the clamp screw /, PI. IV, Fig. 3, it will issue at the bottom 

at the clamp soreAY c, PI. IV, Fig. 1, provided, of course, c be electrically
METHOD OF VOLUME MEASUREMENT. 33

connected with the bottom of the fusion tube. This is easily clone by 

placing-the fusion tube on a plate of platinum above G-, and connecting 

this with c by means of a platinum, wire, as is indicated in the figure.

It is, however, very convenient to register the contact of ZZ and d 

telephonically, and this maybe easily done by using the intermittent 

current of a small inductor like that of Kohlrausch. Contact then 

evokes a loud roar in the telephone, and the observer's attention is 

not further distracted. The adjustment is quite delicate, and if the 

glass ZZ be sticky, the drawing out of a thread is indicated by a gradual cessation of the noise in the telephone, etc. In fact, the character 

of the fusion may be pretty well inferred in this way. The instrument 

is available almost as far as 400°, at which time, however, the furnace 

is dark, and cathetometric measurement is no longer possible.

Care should be taken to secure small sparking distances, for this 

quantity will vary with the temperature of the gas in the furnace.

If the expansion of the rock be known, and the tube del sunk deeply 

into the mass, it is clear that the present method admits of a measurement of the relation of electric resistance and temperature. I mention 

this, believing that a suitable method for temperature measurement 

may be thus available.

Elsewhere 1 I have already speculated on the character of the changes 

of electrolytic resistance referred to temperature. Should a hyberbolic 

law indeed apply, high-temperature measurement would be effectually 

promoted.

METHOD OF MEASUREMENT.

29. Consecutive adjustments. Thus far it has been my object to study 

the contraction of rock only. For this purpose the graduated faucet is 

turned on full and the furnace fired as far as 1,400° or 1,500°, when the 

first measurements are taken. With this end in view the length, of the 

fusion tube is first accurately measured by the cathetometer observations at the bottom and the top. The telescope is then left adjusted for 

the top and the vertical micrometer (centrally adjusted) screwed down 

until its lowest point is just in contact with the crosshairs. After this the 

micrometer is further screwed down until the telephone registers a contact between the meniscus of the molten rock and the platinum micrometer tube. The difference of readings gives the depth of the meniscus 

below the top plane of the fusion tube. I usually repeated this measurement three times and then raised the micrometer screw again.

Thereupon the temperature measurements were-made by connecting 

the terminals of the zero method consecutively with the upper, the middle, and the lower thermocouple.

Finally the cathetoineter measurements of the length, of the fusion 

tube and the micrometer measurement for depth of meniscus were again

1 Am. Jour., Vol. XLU, pp. 134-135,1891,

Bull. 103 3
34 FUSION AND PRESSURE. [BULL. 103.

repeated, the latter three times. Properly uniform heating presupposed, 

it was permissible to regard the mean of the two sets of length measurements as coincident with the intermediate temperature measurement.

This done, I usually waited ten or fifteen minutes to make another 

complete measurement under better conditions of constant temperature.

The graduated stopcock was then partially closed by a proper fractional amount, and after waiting fifteen minutes or more the same 

measuring operations were gone through with as before.

This I continued until the slag became sticky and solidification imminent, when longer waiting and greater slowness in changing the temperature is essential. Fortunately the observer can note the state of 

things very accurately; for when the point of solidification is approached 

a thread of the magma is drawn out of the fusion tube by the ascending 

micrometer tube until it breaks to form a rounded coating on the end 

of the tube. As temperature decreases, even by small amounts, the 

time that it takes to break and round off increases until finally this 

pulling out of a thread ceases and the enamel on the end of the micrometer tube does not change its form, being solid. It is at this point 

(1,095°) that the marked contraction of the molten mass in the tube 

occurs.

Having waited loug enough for the lowest position of the meniscus, 

temperature may then be varied in larger steps again.

When the inside of the furnace has become dark, measurement is no 

longer possible. I then allowed the whole arrangement to cool over 

night, and the next morning determined both the depth of the solid 

meniscus by ordinary contact micrometric measurement, as well as* by 

filling the top of the tube with water, and computing its bulk. This 

gives me iny fiducial or normal volume.

To fill the fusion tube with rock at the outset of the work is a tedious 

operation. The material is added gradually in coarse grains, in proportion as the charge melts down, and after the tube is full some time 

must be allowed to insure the escape of air bubbles.. Inasmuch as the 

fusion tube can at first be easily slipped out of its clay envelope, it is 

well to pack it as full of rock as possible before heating it.

30. Computation. Let the linear expansion of the platinum fusion 

tube be given by 1=10 (!+/(<)), where I and Z0 are the lengths at t degrees centigrade and at zero, respectively,, and where f(t) is a function 

of temperature. Let A and A 0 be the depths of the meniscus below the 

plane of the top of the fusion tube, and v and v0 the volume of the inclosed molten magma, at t degrees centigrade and zero, respectively. 

Then if (1 +f(t) ) 3 is nearly enough equal to 1 + 3f(t) ; if the expansion 

constants of both platinum tubes be the same; and if in consideration 

of the small motion of the micrometer tube and the high temperature 

in the furnace, the air temperature above and outside of the furnace be 

nearly enough equal to zero, since vt/v0 = (l0 A) (!+/(£) Y/(10 <*<>). 

(1) I......'. (vt-v0 )lvu=3f(t) + (A0 -/) (1 + 3f(t) )/(Z0 -/l0 ).
BARUS.] METHOD OF VOLUME MEASUREMENT. 35

Here 3/(<) is directly given after each observation as (Itt l0 )/lo, or it 

may be computed by some smoothing process from all the data as a 

whole.

The equation therefore gives the actual expansion of the rock in 

terms of unit of volume of solid rock at zero. If this be multiplied by 

the specific volume at zero, the absolute expansion is obtained.

An inspection of the equation shows that in the factor A 0 A, the 

micrometer value of the lengths A. is to be inserted in both cases, supposing the contour of meniscus to remain similar to itself; Avhereas in 

?0 ^0 the value of A0 determined from bulk measurements of the space 

at the top of the cold tube is suitable, since the tube is squared off 

below. **

With this it is interesting to compare the results to be obtained in 

case of a float. If A be the height of the column of magma; h the submerged depth of the cylindrical float or bucket with flat base; and if 

fiA=At A0 , <5 11=1^ h0, Sv=:vt v0 , etc., for the temperatures t and t0 

respectively, then

where d R is the rise of the float and I the length of the fusion tube. 

'From this equation it appears at once that the float shortens the effi-! 

cient length of the tube. Moreover, there is serious difficulty of properly determining A in this case. Hence, in vie\v of the capillary and 

other errors encountered by a swimmer in a viscous liquid ; the ease 

with which platinum at white heat welds with platinum vitiating the 

forms of both tube and swimmer; the tendency of air bubbles to accumulate around the latter and the probable utter failure of this method 

in indicating the passage from liquid to solid, induced me to prefer the 

other method. In case of a swimmer the observer does not surely know 

Avhat he is measuring. . » 

31. Errors. First among these the lack of uniform temperature from 

the bottom to the top of the fusion tube may be mentioned. Moreover, 

only in the case of very slow changes of temperature is this quantity of 

like value from the axis to the circumference of the tube. I endeavored 

to meet these conditions. Moreover, since the temperature is actually 

measured at three points along a vertical, and the platinum tube is surrounded by the relatively nonconducting clay tube, I do not believe 

that serious discrepancy can here be apprehended. Specific inquiry 

will be made in the next paragraph in connection with the data obtained. 

Here I need only remark that it is unfortunate that the tube shows a 

tendency to be less hot at the top than at the bottom : for it is in the 

interest of thoroughly compact solidification that the tube cool from 

below upward. A column which cools first at the top is put into a 

state of dilitatiorial strain after the manner of a Rupert drop, so that 

vacuities are left within the mass and the solidification contraction is
36 FUSION AND PRESSURE. [BOLL. 103.

obtained too small in value. I think a remedy for the difficulty in 

question will be fouucl by feeding the upper burner from an independent 

gas supply.

Indeed I have frequently noted lateral funnel-shaped holes several 

millimeters in diameter and as much as 1 centimeter or more deep, terminating in the smooth surface of the meniscus. It is also possible that 

bubbles congregate under the surface of the molten magma, without 

breaking through it, giving rise to these cavities in the cold column. I 

have already stated that the ejection of gases on solidification is of 

very common occurrence.

At very high temperatures (say above 1,500°) I found the meniscus 

to gradually sink in depth even when temperature remained constant 

or rose in value, § 33. This may be due to the escape of bubbles in the 

thin liquid, or it may also be due to the fact that the tube is now insufficiently rigid to withstand the pressure of a column of molten rock 25 centimeters high. Examples will be given below, from which it appears that 

the meniscus, caet. par., does actually sink from day to day conformably 

with changes of length of the platinum tube. I suspect, therefore, that 

the clay tube which envelopes the fusion tube, besides acting favorably 

as a nonconductor, contributes to the high temperature rigidity of the 

system. After several heatings the platinum, tube can no longer be 

removed trom the clay tube, into which it now fits tightly, without 

breaking the latter.

It has been assumed that the meniscus remains similar in form at all 

temperatures. This can only be partially true. The fused rock wets 

platinum so thoroughly, however, that convex forms of meniscus need 

never be apprehended. Indeed there is a tendency to flow or creep into 

crevices. After solidification, however, the meniscus is apt to be drawn 

down so as to be relatively deep near its center. Here is, therefore, an 

, error which counteracts the tendency to dilitational strain, It is almost 

futile to make allowance for these discrepancies, but the micrometrically measured depth of the solid meniscus may be as much as -2 centimeter or -3 centimeter deeper than the mean surface computed from 

bulk.

Although too much reliance must, therefore, not be placed on the 

behavior of the solid state, yet the values are redeemed from the character of mere estimate, because the expansion of the platinum and its 

solid glass core are so nearly alike. This is a particularly fortunate 

chance, whereby the strains imposed on both the metal and the glass 

during cooling do not probably exceed the limits of elasticity of either. 

(§§ 33, 34 35.) From all of this it follows that the cooling of the furnace 

must take place so slowly as to give the viscous content of the fusion 

tube full time to adjust itself free from strain. Particularly are these 

precautions necessary near the solidifying point. In such a case experiment shows that the platinum tube is not dragged along appreciably by the solidifying magma, and the results retain a degree of trust
BARUS.] CONTRACTION OF DIABASE. 37

worthiness much beyond what was to be anticipated, even in the solid 

state. At the same time dilitatioual strain is reduced to a minimum. 

In how far this has been accomplished satisfactorily can always be seen 

in the degree of uniform contraction of the platinum tube.

Another serious consideration is the allowance to be made for the expansion of the platinum probe dd of the vertical micrometer. The 

expansion as estimated above is too small, for it is not merely the amount 

by which the probe is lowered that is subject to expansion, but a considerable length of metal above the furnace passes from a lower to a 

higher temperature. Consecutive values for the depth of the meniscus 

will thus differ appreciably, the later ones being larger as a rule than 

the earlier ones. I hope, however, in the future to obtain, an estimate 

of this discrepancy by measuring an amount of thrust through the sight 

tube with the cathetometer, and comparing this value with the corresponding value to be read off on the vertical micrometer. I have thought 

of maldng the micrometer screw hollow and providing it with an internal 

circulation of water; but this would be difficult to accomplish.

RESULTS.

33. Arrangement of the tables. In the following tables 10 and r0 denote 

the length and radius of the cold platinum fusion tube, and ^'0 the bulk 

value (water measurement) of the mean depth of the meniscus, the 

/measurement being made on the day after the fusion experiments. The 

temperatures at the bottom, middle, and top of the fusion tube are given 

under 0], 02) 03, respectively, and 0 is their mean value, observed at the 

time given. For each value of 0 two data for the expansion of the rock, 

the volume expansion of the tube, and the actual expansion 8V/V0 of 

the rock are given, and they were obtained before and after the temperature measurement. Here V-V0 is abbreviated dV and V0 is the 

volume of the solid rock at zero. The data enclosed in parentheses 

show that in this case the value applied for the expansion of the tube is 

obtained as a mean result of all the measurements made. Otherwise 

the value directly observed was applied.

33. Contraction of diabase. Tables. The results of my first series, 

being of inferior accuracy, will be omitted. Table 12 contains the 

results for the second series of experiments made on October 18,1891. 

Here, too, the precaution of alternating volume measurements with the 

temperature measurements was not yet applied and the values given 

are less nearly coincident.
38 FUSION AND PRESSURE. [BULL. 103.

'E 12. Contraction of diabase. Second series.

l0 =25'49<--">; Ao^-SO"" 1 ; r,,= -75"'"

0i

e,

03

°c

. 1513

1536 

1492 

1538 

1566 

1528 

1451 

1475 

1515 

1204

1194 

1208 

896 

864 

855 

804 

724 

783

Mean. 

0

°C 

1514

1544

1480

1202

872

770

20

Apparent 

volume expansion of 

the rock.

 0442

 0431 . 

 0421 

 0379 

 0374 

 0369 

 0345 

 0343 

 0342 

 0302

 0304 

 0302 

 0074 

 0050 

 0025 

 0016

 oooo

Volume 

expansion 

of the tube.

.0411

 0399

 0378

 0300

( -0290) 

 0282 

 0201 

( -0183) 

 0165 

 0141 

 0130 

 0120 

 OOHO

SF/Fu

Mean.- 

<57/Fu

 0853

 0842 

 0832 

 0778 

 0773 

 0768 

 0721

 0602

 0594 

 0584 

 0275 

 0233 

 0188 

 0157 

 OH6 

 0138 

1 -0000

Time.

Minutes. 

0

25

50

75

100

130

Next day

Remarks.

Liquid. Viscousextension of tube?

Liquid. 

Liquid.

Solidifying, chilled 

exteriorly.

Chilled solid. 

Solid. 

Cold.

Taking each of the three values of dV/V0 at 1514°, 1544°, 1480°,it 

is seen that the members of each set successively become more coincident. Moreover, the sweep downward and to the right of the means 

of the individual values of d V/ T70 is such as to indicate either that 

the tube sagged viscously or that the magma ejected bubbles or 

changed the figure of its meniscus. It seems to me that the platinum 

tube underwent stretching until it was finally restrained by the clay 

tube enveloping it. Rejecting the first datum, the mean volume expansion of the liquid is '000050 per degree, a value which agrees very well 

with the subsequent work.

The passage from 1202° to 872° is abrupt, indicating that a melting 

point has been passed. Moreover, the wide divergence of the three 

data for d V/ V0 at 872°, shows that the cooling took place far too 

rapidly, so that the temperature of the rock must have been much 

higher than the thermocouples indicate. Finally the mean volume expansion of the solid magma be^v 872° is about -000020 per degree, a 

value which also agrees very well with the work below.

If the solidifying point of the magma be 1095° (the value found in §§ 

34,35) then the contraction on solidifying may be estimated at 3 per cent. 

Thus it follows with certainty that diabase contracts on solidification 

and that its fusion behavior must be of a thoroughly normal type.

The amount of solidification contraction is, however, too small if too 

rapid cooling actually produces a strain of dilatation. For the same 

reason the values of 6 V/ V0 for the liquid state, though correct in 

their relations to each other, must be uniformly too small, for the factor 

TO used is too large. All this is proved directly by the next two tables, 

but it may be inferred here from the contraction curve of the platinum, 

tube. This shows reasonable uniformity of contraction as far as 900°, 

after which, however, there is a break to much smaller rates of con-
BAttUS.I CONTRACTION OF DIABASE. 39

traction, showing I think that the platinum tube has been dragged 

along by the too rapidly solidifying magma.

34. Contraction of diabase. Tables and chart. The data of my third 

series of experiments, made on October 20, 1891, are given in table 13. 

The precautions for slow cooling were fully taken, and the solidification 

point is now sharply apparent.

TAHLE 13. Contraction of diabase. Third scries. 

L = 25- 4GG<"n; X« = 1- 424cm ; ra = -75«m .

«l .

et 

03

°G. 

1360 

IMG

128G 

1304

11G3 

1107

1108

1097 

1093

1089

1102 '

1088

929 

897

863

461 

433

510

Mean. 

B

°G. 

138G

1300

11GG

1093

1095

896

468

20

Apparent 

volume expansion of 

rock.

 0452 

 0454

 Oi37 

 0438

 0406 

 0409

 0376 

 0333

 0014 

 0013

 0000 

 0002

 -0004

 0000

Arolume expansion of 

the tube.

 0358 

( -0356)

 0340 

( -0334)

 0297 

( -0300)

 0270

/ .0901 \

 0273 

( -0282)

 0211

 0081

 0000

<5 Fi/Fo

t v,/v0

 0810 

. -0812

 0777 

 0778

( -0772)

 0703 

 0706

( -0706)

( -0709)

 0646 

 0603

( -0657)

(. 0614)

.0288 

.0286

(. 0290)

(. 0295)

.0211 

.0213

 0077 

 0081

 0000

Mean.

« T/n

 0811 

( '0809)

 0778 

( -0772)

 0704 

( -0707)

 0646

( -0657)

 0287

 0212

 0079

 0000

Time.

Minutes. 

0

23

53

86

111

157

185

Next day.

Kemarks.

Liquid.

Liquid.

Sticky.

Very sticky.

threads.

ally.

Solid.

Solid,

Solid.

Cold.

Hock, mean actual expansion, solid, 0° 1000°, -0000250.

Bock, mean actual expansion, liquid, 1100° 1500°, -0000470.

Bock, expansion on fusion (1095°), -0390.

Rock, mean apparent expansion, solid, 0° 1000°, '0000007.

Bock, mean apparent expansion, liquid, 1100° 1500°, -0000205.

Tube, mean expansion below 1000°, -0000240.

Tube, mean expansion abo've 1100°, -0000265.

These values are fully represented in the chart, Plate V, where the 

actual expansion is given by the heavy curve dcbef,t\ie ordinates being 

the volume increments and the abscissae temperatures. The apparent 

expansion of the rock is shown by the light curve lie gh, the ordinates of 

the solid contour lie being nearly zero, so that the tube and contents expand nearly at the same rate, whereas the liquid contour gh follows 

with a marked jump and shows great uniformity. Finally the expansion of the platinum tube is represented by the dotted curve dc a i. 

The exceedingly small break at a, which indicates the amount of drag 

or shortening of the length of the platinum tube by the solidifying rock, 

shows how well the operation of cooling has here been conducted, and 

proves the results to be trustworthy throughout.

One of the important results obtained from the chart is the occurrence 

of a sharply-defined solidifying point at 1093°. Here, therefore, is a
40 FUSION AND PRESSURE. [BULL. W3.

method by which this point of the rock can be defined free from nonintrinsic tests. '

Finally, it may be noted that so long as the magma is liquid, the 

distribution of temperature along the fusion tube is fairly constant, and 

and is usually hotter at the top. After this the discrepancy increases, 

probably from lack of convective conduction of the solid magma.

35. Contraction of diabase. Tables and chart. The data of my last 

series of experiments, made on October 21, 1891, with all precautions 

necessary, are given in Table 14. Two complete sets of result for each 

step of temperature are given.

 TABLIS U. s-Contraclion of diabase. Fourth series. 

Z» 25.447cm ; A' 0 =1.220 ; ra .75""

9. 

62

03

C°.

1374 

1394

1395

1415 

1431

1318 

1324

1315

1304 

1308

1304

1204 

1189

1170

1177 

1158

1153

1138 

1109

1090

1117 

1088

1072

1109 

1081

1086

946 

903

893

900 

827

837

20

Mean. 

B

;'°c.

1388

1421

1319

1305 .

1190

1163

1112

1092

1092

914

855

Apparent 

volume expansion of 

rock.

 0403 

 0404

 0407

 0394 

 0387

 0383 

 0390

 0357 

 0355

 0355

 0339 

 0344

 0200 

 0155

 0091

 0033 

 0005

 0013 

 0006

 0003 

 0003

 0000

Volume expansion of 

the tube.

 0357 

( -0356)

 0362 

( -0364)

 0341 

( -0339;

 0350 

( -0335)

 0310 

.( -0305)

 0299

 0286

 0275 

( -0280)

 0282 

( -0280)

 0213

 0199

 0000

sy, i TO

SV2 /Y0

 0760 

 0761

/ -fi7^Q\

( 0760)

 0768 

 0771

( -0771)

/ .fl77Q\

 0734

 0727

( -0733)

( -0726)

 0733 

 0740

( -0718)

( -0725)

 0673 

 0671

( -0662)

( -0660)

 0655 

 0649

( -0655)

( -0649)

 0625

( -0625)

( -0630)

 0475

 0366

( -0480)

( -0435)

( -0371)

 0315 

 0287

/ .AQ1O\

( -0285)

 0226 

220

 0202 

202

 0000

Mean. 

AVIV.

 0760 

( '0760)

 0770 

( -0771)

 0731

/ .n73fi\

 0736 

( -0721)

 0672 

( -0661)

 0652

 0028 

( -0628)

 0475 

( -0480) '

 0287 

( -0285)

 0223

 0202

 0000

Time.

Minutes. 

5

20

50

. 05

90

105

128

151

175

198

210

Remarks.

Liquid.

Liquid.

Liquid.

Liquid.

Sticky.

Very sticky.

in threads.

Top encrusted.

Solidifying.

Solidifying.

Solid.

Solid.

Cold.

Bock, mean actual expansion, solid, 0° 1000°, -0000250. 

Eock, mean actual expansion, liquid, 1100° 1500°, -0000468. 

Eock, mean apparent expansion, solid, 0° 1000°, -0000005. 

Hock, moan apparent expansion, liquid, 1100° 1500°, -0000218. 

Tube, mean expansion below 1000°, -0000235. 

Tube, mean expansion above 1100°, -0000260. 

Eock, expansion on fusion, (1093°), .0340.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. V

!09

08

07

ctiorv.

06

05

03

02

~^~A} ^parent 

Contr xenon.

9

Ol

&

.k

500° 10OO°

CONTRACTION OF MOLTEN DIABASE, CONTINUOUSLY FROM LIQUID TO SOLID.

1500°
BARUS.] . CONTRACTION OF DIABASE. 41

These data are given in the chart, PI. VI, Fig. 1, on the same plan as 

in the preceding case. The inferences to be derived are identical with 

those of tlie preceding paragraph. The sudden contraction of the rock 

on solidifying is of smaller value here, but this is to some extent compensated by the greater longitudinal compression of the fusion tube, 

as shown at a in the curve c ai. It is interesting to note that in both 

series 3 and 4 the first length measurement of the tube at the solidifying point of its contents, is smaller than the second, showing the end 

thrust to have diminished in value, while the tube has recuperated 

from its strain. It is also well to note that the sag of tube, as expressed in the cold lengths 25-49 centimeters in the second series, 25-47 

centimeters in the third series, and 25-45 centimeters in the fourth series 

is small, but quite appreciable.

Regarding the differences of A,, (micrometric), and X' 0 (bulk measurement), which is -34 centimeter in the fourth series, '13 centimeter 

in the third series, and -38 centimeter in the second series, the remarks 

made in § 31 apply. Hence the third series is the one in which cooling 

was slowest, and in this the solidification contraction is largest. Lateral fissures opening into the solid meniscus were present in both these 

cases. Regarding the depth ^, of the solid meniscus at the outset, and 

at about the same temperature, 1387°, I found A = -50 centimeter in the 

third series, and A = -62 centimeter in the fourth series, showing enlargement of the volume of the fusion tube.

Finally, as before, temperatures are hotter at the top or fairly uniform so long as the magma within the fusion tube is very liquid. Near 

the solidifying point, however, and thereafter, the top is colder. For 

this reason, since solidification commenced at the top, the data of this 

paragraph show a smaller solidification contraction than in the last 

instance.

36. General remarks. The charts show how important it is to measure 

the expansion of the fusion tube, which, if neglected, would distort the 

liquid expansion fully 50 per cent. Moreover I have no doubt that 

when fusion is made in clay crucibles which are apt to become friable 

after heating, the clay on cooling is quite at the mercy of the more 

tenacious slag within, and changes its volume accordingly.

Again even in case of slow cooling solid contraction tends to express 

itself as a dilatational strain, and if gas bubbles are ejected by rocks on 

solidifying solid volumes will be found too large and the solid contractions, etc., too small. Hence I place greatest reliance in the solidification contraction given in. the third series, the value being 3-9 per cent.

Naturally, I also made special experiments on the floating of solid 

rocks on the molten magma, cf. §20. To my surprise such flotation 

always occurs, notwithstanding the fact that originally the cold rock 

must be 8 per cent + 10 per cent more dense than the molten rock, 

since it is both solid and cold as well as possessed of organized rock 

structure. It soon appeared, however, that the cause of such flotation
42 FUSION AND PRESSURE. [BULL. 103.

is crudely mechanical, since the rock in. virtue of its weight simultaneously hollows out a cavity and chills it, thus forming a little solid boat 

in which it floats on the very viscous slag below. This is shown in 

Plate VI, Fig. 2, where a is the body of rock, AA the molten magma, 

and bb the solidified bowl-shaped skin. It may be observed that flotation is assisted by viscous friction of the blanket bb on the magma A A 

which supports the blanket and keeps it distended. I then attempted 

to make Mess and Winkelmann's " Fundamental-versuch" by submerging the rock; but here both on account of the intense white glare of 

the furnace and the tendency to chill at the surface of the magma 

during the operation I was not able to reach any definite point of view.

Kesults for thymol are given in Plate VI, Fig. 3, for comparison. §38.

37. Fusion and solidification alternating. To corroborate the above 

work, I made some experiments by measuring the expansion on fusion, 

as well as the contraction on solidification. These are contained in 

Table 15, where the notation is the same as above. The zero lengths 

(Z0 , A 0 , etc.), were taken from the above work, as was also the expansion 

of platinum. '

TABLE 15. Fusion and solidification alternating.

Time.

Minutes. 

20

45

70

05

127

165

fln' 

0 2

<>3

o 

1139

1 1 73

1235 

1246

1234

1254 

1275

12G6

1285 

1294

3280

1157 

1176

1188

1146 

1125

1132

Menu

e

o 

1158

1239

1265

1280

1174

1134

(iv/va ) 

X10 1

332 

343

511 

614

664 

671

678 

681

604 

591

425 

404

Time.

Minutes. 

195

225

240

2GO

280

o, 

0 2

<>3

0

1059 

1086

1097 

10GG

1039

1167 

1190

1192

1239 

-1246

1232

1087 

1115

1138

Moan 

0

o 

1086

1067

1183

1239

1113

(<5y « ) 

X10J

302

274 

271

338

T73

5li8

328

The difficulty with these experiments lies in the insufficient time 

allowed for fusion and solidification (§§33-37). In the former case irregularities are unavoidable, since it is impossible to heat a solid rod of rock 

uniformly throughout its length. The high solidifying point, here, 

probably follows from the fact that the fusion was not complete. This 

is seen in Fig. 3, where the individual data are marked by numerals indicating the time at which the observation was made, and where the 

first cycle is indicated by a heavy line, the second by a light line. I 

suspect, therefore, that in rocks melting and solidifying points are diferent and may be 100° apart. Hence the large contraction at a definite 

degree of temperature observed above, was due to very slow cooling of 

an under-cooled mass.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. VI

Rock, 

Actual Contraction.

CONTRACTION OF MOLTEN DIABASE, CONTINUOUSLY FROM LIQUID TO SOLID.
BARUS-l VOLUMETRY OF THYMOL. 43

The Amount of volume contraction agrees in both cases with, the above 

data, and this is the chief point at issue.

INFERENCES.

55. Comparison with thymol. Since the fusion of rocks like diabase 

is thus thoroughly normal, it follows that melting point must increase 

with pressure. It is well to examine tentatively into the nature of this 

relation, and for this purpose I have draAvn certain unpublished results 

of mine for thymol, on the same scale used for the rock. In PI. VI, Fig1 . 

3, m'n'o'p' shows the contraction of thymol at its melting point, where 

the substance is liquid along o'p' and solid along m'n'. Similarly, mnop 

shows the contraction of thymol at 0°C. These results indicate that

1000

04-

 03

02

14! M)'

Fio. 3. Cyclic volume ciuiuges produced by alternate fusion and solidification of rock magma

(diabase).

the solidification contraction decreases in proportion as the thermal 

expansion ([<J( V/ V0 )fd6]6 where 0 denotes temperature) decreases. The 

solidification contraction of thymol, therefore, like its coefficients of 

expansion, is larger than the similar variable in the case of rock. The 

relations are such that if liquid thymol could be cooled down to 25° 

it would then shoAv the same solidification contraction as the silicate.

39. Lower critical temperature. Analogously the compressibility of 

the rock will show decidedly larger values than in organic bodies; and 

hence it also follows that whereas the lower critical pressure liquidsolid of naphthalene, for instance, should, according to ray experiments, 

lie somewhere in the region of 10,000 atmospheres, the corresponding
44 FUSION AND PRESSURE. [BULL 103.

pressure in the case of rock magma must be indefinitely higher. In 

other words, the consecutive isopiestics of the magma must lie very much nearer together than the corresponding isopiestics of naphthalene, 

supposing the pressure to vary in like steps in both cases.

40. Melting point and pressure. From this, however, it does not by 

any means follow that the relation of melting point to pressure will be 

different in the silicate and in the carbon compound. In the latter 

case, data for normal fusions are available in case of wax, paraffin, 

spermaceti, and naphthalene, and for these dT/dp, the relation of melting point to pressure, lies within the narrow margin of-020 to -036, data 

moreover which even for the same substance1 are subject to variation. 

Thus I found that in naphthalene dT/dp varied from -027 to -035, according as melting points or solidifying points were suitably considered. 

Since, therefore, the fusion both of the organic bodies and the silicate 

is alike in character, it is probable that the same factor dT/dp will correspond to both cases. The direct consideration of these questions will 

be the subject of the next chapter.

1 See my work cm naphthalene, Am. Journal Sci., vol. 42,1891, p. 144 et seq.
CHAPTER III.

THE THERMAL CAPACITY OF IGNEOUS ROCK, CONSIDERED IN 

ITS BEARING ON THE RELATION OF MELTING POINT TO PRESSURE.''

PRELIMINARY REMARKS.

41. Introductory. The present experiments are in series with the 

volume measurements of my last chapter, and the same typical diabase, 

§ 18, was operated upon. Since it is my chief purpose to study the 

fusion behavior of silicates, more particulurly the relation of melting 

point to pressure, the observations (700° to 1400°) are restricted to an 

interval of a few hundred degrees on both sides of the region of fusion. 

The solid locus found, however, is one which would be nicely tangent 

to an initial specific heat of about -2, the value which probably obtains. 

The liquid locus is again indicative of a transitional temperature.2

42. Literature. Experiments similar to the present, but made with 

basalt, were published quite recently by Profs. Eoberts-Austen and 

Blicker.3 In view of the normal behavior occurring throughout my 

own data, the irregularities obtained by these gentlemen in case of different methods of treatment (heating in an oxidizing or reducing atmosphere, repeated heating, sudden cooling, etc.), the anomalously large 

specific heat between 750° and 880°, where, basalt is certainly solid, and 

the absence of true evidences for latent heat 4 make their results somewhat startling. Basalt is lithologically so near akin to diabase that 

one would anticipate a close physical similarity in the two cases. Unfortunately, the account given of the work with basalt is meager, and 

detailed comparisons are therefore impossible. I will only state that as 

nobody had then compared the platinum-rhodium couple with the air 

thermometer, I should not have regarded a standardization by means 

of a single melting point sufficient.

.' Cf. Am. Journal Sci., vol. 43,1892, pp. 50,57. 

' 2 Am. Journal Sci., vol. 42,1891, p. 145.

3Koberts-Austen and Riioker: Phil, Mag., vol. 32,1891, p. 355.

 Supposing basalt to melt below 1200°. The authors state that the specific heat of basalt is ureatei 

in the liquid than in the solid state, but no remarks are made as to -whether the rock was fused al 

their higher temperatures or not.

45 
46 FUSION AND PRESSURE. [BULL. 103.

APPARATUS.

43. The rode to be tested. About 30 grams of diabase were fused 

in a small platinum crucible, together with which they were to be 

dropped into the calorimeter. Two of these charged crucibles were in 

hand and used alternately. After removing the (cold) crucible from the 

water into which it had been dropped at red or white heat, the surface 

of the glass usually shows a smooth unfissured gloss. This, however, 

is only apparent, for after drying and weighing, the mass is often found 

to have increased in weight fully 5 per cent. I was at first inclined to 

believe-that this was due to water chemically absorbed by the viscous 

magma; but the water is only mechanically retained, for it passes off completely after twenty-four hours' exposure to the atmosphere, or by drying 

at 200° for, say, 30 minutes. Hence, at the beginning of each measurement I weighed the crucibles again, having thoroughly dried them at 

200°. The solid glass dropped into water at low red heat soon shows 

a rough and fissured surface, and changes in color from black to brown, 

possibly from the oxidation of the protosilicate to the scsquisilicate of 

iron. The effect of this change (if it be a chemical change and not a mere 

change of the optical character of the surface) is inappreciable, at least 

by the following calorimetric method.

Throughout the course of the work the charge was neither changed 

nor replenished.

44. Thermal capacity of platinum. Since the charge, of molten rock 

and the crucible are submerged together, it is necessary to know the 

heat given out by the known weight of the platinum. .Data for this 

purpose ha\e been published by Violle. 1 In these the high temperature specific heat at t° is given as -0317 + -000012?, whence the increase 

of thermal capacity from zero to the same temperature is (-03174- 

 000006^) t. This is the allowance I made per gram of platinum crucible.

45. Furnace. Inasmuch as heat is rapidly lost by radiation from the 

white hot slag, it is necessary to transfer the crucible from, the furnace 

into the water swiftly. Trap-door and false-bottom arrangements, 

which at first suggested themselves, were discarded, because the 

mechanism clogs the furnace, interferes with constancy of temperature, 

and is too liable to get out of order.

The furnace adopted is shown in PI. VII, Figs. 1 and 2, in sectional 

elevation and plan. The body consists of two similar but independent 

half cylinders A A and BB of fire clay, properly jacketed and closed 

below, which come apart along the vertical plane cccc. The lid LL, 

however, is a single piece, fixed in position by an adjustable arm (not 

shown). Each of the halves of the body of the furnace is protected by a 

thick coating of asbestos (70, DZ>, and by a rigid case of thick sheet 

iron, EE, FF; clamp screws </,- </, #, </, pass through this in such a way as

Wiolle: O.K.., vol. 85 1877, p. 543; vol.87, 1878, p. 981; vol. 89, p. 702,1879; Phil. Mag., (5), iv,p.318, 

1877.
U. 8. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. VII

G

Fiy.Z.

FURNACE FOR CALORIMETRY, WITH THE BODY K (CRUCIBLE), THE PYROMETER tt, AND THE HOLDERS N N IN PLACE. SCALE
BAKUS.] CALOEIMETRY. 47

to liold the fire clay and asbestos firmly in place. The horizontal base of 

the casing .$, P, is bent partially around the two iron slides (r, 0, along 

which the two halves of the furnace may therefore be moved at pleasure 

while the lid L is stationary, as is also the blast burner H, clamped on 

the outside and entering the "furnace through a hole left for that purpose.

The charged crucible is shown at K, and is held in position by two 

crutch-shaped radial arms, JV, JV, of fire clay, the cylindrical shafts of 

which fit the iron tubes P, P snugly and are actuated by twx> set 

screws, jK, R. The two tubes P, P,. moreover, are covered with a nonconductor, and thus subserve the purposes of handles,, by grasping 

which the two halves of the furnace may be rapidly jerked apart. It 

is by this means that the crucible is suddenly dropped out of the furnace into the calorimeter below. Care must be taken to have the arms 

free from slag, as otherwise the crucible is not at once released.

46. Temperature. As in a former case, the temperature of the furnace is regulated at pleasure by forcing the same quantity of air through 

it at all times, but lading this air with more or less gas supplied by a 

graduated stop cock. The amount of gas necessary in any case is 

determined by trial, and observations are only to be taken after fifteen 

or twenty minutes' waiting, when the distribution of temperature is 

found to be nearly stationary. It would h ave been better to have curved 

the bottom of the furnace cyliudrically, so as to surround the crucible 

with a whorl of flame. The temperature of the crucible is never quite 

constant from point to point. I therefore measured this datuni at three 

points, near the bottom, middle, and top of the charge. For this purpose 

the fire clay insulator 11 of the platinum platinum-iridium thermocouple 

ab passing through a hole in the lid is adjustable along the vertical. 

Before dropping the crucible the thermocouple is withdrawn from the 

charge and suspended above it. The cold junction communicates with 

the terminals of the zero method submerged in a bath of petroleum and 

provided with a thermometer.

When the charge is solid, a small platinum tube which has been previously sunk into the molten glass before solidification (see PI. VII, Fig. 

3), enables.the observer to make the three temperature measurements, 

as before. In later measurements I also incased the insulator of the 

thermocouple in a platinum tube, closed below (see PI. VII, Fig. 1), when 

making the temperature measurements for the molten charge. Slag 

at high temperature being a good conductor, it is not impossible that 

hydro-electromotive forces may enter, slightly distorting the thermoelectric data.

When constancy of temperature is being approached the hole in the 

lid L LIB closed with asbestos, and the products of combustion escape 

by the seam in the side. This facilitates manipulation above the furnace. The crucible is visible in part through the seam in question.
48 FUSION AND PRESSURE. [BOLL. 103.

47. Calorimeter. This was a vessel of thin tinned sheet iron, 28 centimeters long and 8 centimeters in diameter, having a water value of 

19 g. cal. and holding a charge of about 1,200 grains of water. The 

inside of the calorimeter was provided with a helical strip running 

nearly from top to bottom. The vessel, contained within a suitable 

environment, was supported on a hard rubber stem, which could be 

grasped below, and served as an axle around which the calorimeter could 

be rotated from without. In this way the water within was churned. 

Three small, hard-rubber rowels near the top gave steadiness to the 

motion. They were fixed to the hollow cylindrical vessel (environment) 

provided with a hollow hinged lid, through both of which a current of 

cold water, at constant temperature, continually circulated. Thus the 

temperature surrounding the calorimeter was at all times given, and the 

correction.for cooling could be found and applied with accuracy. I pass 

by the description of this apparatus rapidly here, inasmuch as I shall 

recur to it in connection with other calorirnetric work. The box of the 

calorimeter with its projecting stem was movable on a small tramway, 

the tracks of which lay at right angles to the slides G G. (PI. VII, Figs. 

1 and 2.) Thus when the measurements showed a sufficiently constant 

temperature in the furnace, the lid of the box was opened and the 

calorimeter rolled directly under the furnace. After receiving the 

crucible, the calorimeter was again rolled away and the lid of the box 

closed, whereupon the temperature measurements were made by aid of 

a sensitive thermometer inserted through a hole in the lid.

I may add here that should I have occasion to extend the work to 

other substances, I would have a bullet-shaped platinum crucible provided with a central tube similar to Fig. 3, made at the outset. In 

this way splashing during the drop of the crucible into Avater would be 

to a great extent obviated.

RESULTS.

48. Method of icork. While waitin g for the temperature of the furnace 

to become stationary, I made the initial measurements for the cooling 

of the calorimeter, in time series. Knowing, therefore, the time at 

which the body was dropped, I also knew accurately the temperature 

of the water into which it was dropped. Just before this the three 

measurements for temperature of the charge had also been made in 

time series. The experiments showed that ten minutes after submergence, the crucible and charge might be safely considered cold, for the 

minimum temperature of the calorimeter was reached after about five 

minutes. Hence the time from 10 minutes to 15 minutes after submerging could be utilized for making the final measurements for cooling. 

Knowing these, I interpolated the rates of cooling for any inter mediate 

times.

Thus while the calorimeter was being constantly stirred, its temperature was measured at the end of every minute. Hence I knew the
BABU8.] CALOBIMETKY. 49

mean excess of its temperature above that of its environment during 

the course of every minute, and was able to add the correspondingallowance for radiation at once. How important this is the tables below will fully show. It may amount to 10 per cent of the total temperature increment. The only drawback against obtaining sharp 

values for the consecutive rates of cooling is to be found in the lag 

error of the thermometer j but this is eliminated in a long series.

The calorimeter was ahvays Aveighed before and after the work, but 

the latter datura was taken. Similarly, as has been stated, the crucible was weighed before and after heating and the latter datum taken. 

Some charge is always removed or added by the thermocouple.

49. Arrangement of the tables. There being two crucibles and two 

tubes (PL VII, Fig. 3), they are distinguished by I and II. In all cases 

r is the temperature of the environment, m the mass of the charge, M

the water value of the. calorimeter (corrected for temperature). & is 

the temperature at the bottom, middle, and top of the charge at the 

time of submergence, for which a mean value is also given. The temperature observed in the calorimeter at the time specified is given under 

0, and a parallel column shows the correction of 6 for radiation. Finally, 

the computed thermal capacity of the platinum crucible and appurtenances (correction /i), and the thermal capacity h of the charge given 

for each of the consecutive times, are found in the last columns. A 

few obvious remarks follow. All data are referred to gram calories.

50. Tables. In the data of the first series (Table 16) only one value of 

& occurs for the liquid state. Moreover, the construction of the furnace was somewhat faulty, not being flat-bottomed. Hence these results 

are of inferior accuracy, and ..their chief purpose is to bear out the 

results of Table 17, which are the best I could obtain.

TABLE 16. Thermal capacity of diabase. Mrst series.

Platinum crucible J, 11-1696; platinum tube J,-985e. 

Platinum crucible II, 11-2716; platinum tube II, -654e.

No.

I

I

IT

r

°C 

10

10

19

Tiino.

minutes.

OK

26

27

Oft

OA

00

36

5

G

7

10

13

16

19

26

27

28

29

31

34

37

40

6

Mean © 

M 

m.

1306°

1145s

38-758

1367°

1202s

33-36B

1378"

1202s

0

°C 

25-90

34-90

36-30

36-60

36-59

36-04

14-92

22-80

25-20

25-50

25-58

oc.oc

25-12

22-16

31-00

31-70

31-42

31-21

30-97

Correction 6

 07

 17

 27

 48

 79

1-10

 ft9

' -06

 11

 20

 P3

 46

 60

 05

 i %

 21

 38

 63

 H7 1-11

correction h.

g. cal.

16-6

17' 0

on* 7

h.

g. cal.

291

342

oce

onq

' 364

OfiK

267

367

070

370

370

370

OAO

346

070

384

384

 ififi

386

Kemarks.

..

S 364

..

( 370

S 385
50 FUSION AND PRESSURE. [BULL. 103.

TABLE 16. Thermal capacity of diabase. First series Continued.

No

I

II

I

II

I

11

I

II

t

°C

1 9

12

12

12

11

11

11

11

Time.

minutes. 

36

37

38

. 39

41

44

47

50

9

10

11

12

14

17

20

93

15

16

17

18

20

23

26

29

1

2 

3

4

6

9

12

15

1

2 

3

4

6

9

12

2

3 

4

5

7

10

13

10

1

2

4

6

9

12

8

9 

10

11

13

16

19

22

0

1199

1163 

1138

iioo

1074 

1060

1021

998 

983

'1035

1025 

1015

889

880 

872

827

827 

833

Mean © 

Jf 

in.

1337°

1196s

32-226

1274"

11906

29-16R

1166"

. 11956 

32-226

1678°

1196s 

29-166

1001"

11968 

32.23s

1025"

11958 

29-166

880°

1198 B 

32-246

829°

11926 

29-166

6

°C 

14-55

22-40

24-00

24-80

24-79

24-68

9/1. Kr

24-40

21-92

28-50

30;60

30-03

30-42

Uft-99

9Q*Qft

14-87

22-60

23-30

23-37

23-21

23-15

22-98

21-16

27-20 

97'fift

27-90

27-76

27-59

27-41

27-25

14-89 20-'40 

21-40

21-58

21-58

21-45

21-31

19-76

25-00 

25-90

26-20

26-10

25-90

25-55

16-19

21-80 

21-90

21-94

21-83

21-70

91 iriO

20-07

24-50 

24-90

24-00

24-85

24-67

24-51

24-39

Correction 9

 02

 07

 12

 23

 54

 69

 05

 13

 21

.OH

 62

,Qfi

no

 03 

 00

 15

 97

 45

 63

 81

 04 

 09

 15

 9K

 42

 58

 74

 02 

 07

 11

 20

 47

 03 

 08

 25

 41

 73 .

 03 

 06

 10

 18

 30

 41

 04 

 09,

 14

 23

 37

 51 '

 65

correction h.

g. cal.

18-0

ifi

16-7

16-4

13-9

15-5

12-0

' 12-1

h.

g. cal.

275

007

368

071

3

70

 17^

07 c

256

312 -

349

356 i^a

OKQ

3"iQ

271 

292

302

308

309

314

314

232

2

^0

266

264

264

263

263

191 

230

2Qg

242

242

242

201 

240

254

255

.253

2

K9

252

198

9AO

206

204

204

204

171

189

191

193

191

190

190

..

f 070

.

-. <i^ft

Solid.

.

\ 311

Solid.

^

f Ofjq

Solid.

.j

( 242

Solid.

\

(. 9<W

Solid. -

.,

( 204

Solid.

^

( 191
BARUB.] ' THERMAL CAPACITY OF DIABASE.

TABLE 17. Thermal capacity of diabase. Second series.

Platinum crucible I, ll-169e ; Platinum tube /,-985c. 

Platinum crucible II, 11-271?; Platinum tube II, '054r

51

No.

II

I

II

II

I

11

I

II

n

i

r

°C. 

]2

12

12

10

10

10

10

10

10

10

0

°c.

12U5

1246

997

995

OQ7

1260

1251 

1243

1354

1333 

1319

954

948 

C42

1364

1354

877

873 

870

1176

1164 

1158

1215

1191

782

780 

780

Mean 0 

H 

in.

1251 °

1189 B 

26-39 s

 993"

1192s 

32-22 6

1251°

1190 e

1334"

11906

oft. 97 K

048°

1186e

09.99 II

1352 °

11946

Oji.ftK e

873"

1191 B 

32.206

1166°

1187 B 

25'97 e

"

1197°

1192C

781°

11898 

32-198

Time.

minutes.

5

7

9

12

15

18

2

3

4

5

7

10

13

3

4 

5

6

8

11

14

1.7

5

6

1 8

10

11

16

19

9

10 

11

14

17

20

23

9

10 

11

14

20

23

0

1

2

3

5

 8

11

5

6

 7

8

10

13

16

19

7

8 

9

10

12

15

18

21

9

10 

11

12

14

17

20

23

6

°C. 

18-94

24-60 

26-05

26-45

26-25

26-08

14-07

20-20 

20-56

20-80

20-80

20-75

20-61

19-34

26-00 

27-00

27-20

27-03

26-86

26-69

26-49

13-78

20-60 

21 -«0

99 '90

22-23

99- V

91 .Q'

21-79

20-24

20-00 

26-40

26-42

2fi-22

2(1-01

25-81

17-18

23-70 

24-80

25-42

9*v10

25-01

24-82

14-83

19-80 

20-30

20-60

20-38

20-23

v 20-13

17-40

24-30 

24-70

24-80

24-75

24-55

24-39

24-21

14-38

20-00

on. on

21-50

21-55

21-40

21-20

19-36

24-00 

24-20

24-1.8

24-13

23-81

23-C1

Correction 8

°C.

 04 

 10

 16

 30

 50

 69

 88

 01 

 03

 05

 10

 16

 22

 04 

 10

 16

 27

 45

 62

 80

 03 

 09

 15

 28 '

 47

 65

 84

 05 

 12

'19

 : !'<

.e,^

 94

 04 

 10

 16

 29

 49

 fis

 87

 02 

 06

 09

 16

 26

.36 46

 04 

 10

 16

 27

 44

 60

 77

 03

. 10

 21

 35

 49

 62

 05 

 12

 19

 33

 54

 74

 94

Correction h.

g. cal.

20-6

13-8

20-8

22-4

13-0

23-1

11-9

*

19-2

19-9

10-4

7t.

g. cal.

236 

305

329

339

341

340

341

213

997

237

239

239

237

285 

333 <u*>

342

343

343

342

288

366

373

377

378

378

201 

218

225

227

227

227

227

277

351

368

360

367

367

173 

193

205

203

203

201

201

281 

301

308

311

309

309

309

239 

278

312

319

318

318

318

163 

173

175

. 178

179

181

181

Liquid.

j

( 340-5

Solid.

 j

( 238-3

Liquid .

^ .

( 342-5

Immersion

Liquid.

 j

V 376-6

Solid.

1

( 226-6

Liquid.

^

V 367-0

Solid.

^

( 202-1

Liquid.

 j

1 309-5

Liquid.

\

S 318-5

Solid.

S 179-7
52 . FUSION AND PRESSURE. [BULL. 103. 

TABLE 17. Thermal edacity of diabase. Second series Continued.

No.

II

I

I

II

I

II

T

°c.

10°

10

11

11

11

11

©

°c.

1204

1195

1 1 QO

1177

1170 

1166

1106

1094 

1088

1262

1244 

1238

1237

1216 

1202

1224

1215 

1205

Mean @ 

H 

m.

1194°

1195s

oc.Qn<7

/

1171°

1192s 

32-206

1096"

1.195* 

32-215

1248"

11916

1218"

1188s

1215°

1185s 

25-57.6

Time.

minutes. 8-5 . 

10 

11

19

14

17

20

23

8

9 

10

11

1 °.

16

22

0

1 

2

3

8

11

14 -

1

2

0

4

6

g

12

15

8

9

10

11iv

16

19

22

5

6

7

8

10

13

16

19

6

°C. 

14-54

21-60 

21"70

91 -7fi

21-63

21-49

91 °.fi

21-22

19-88

25-20 

28-20

28-30

28-07

27-95

27-62

27-37 *

16-28

22-70 

23-60

23-75

23-54

23-39

23-24

19-72

25-90 

26-60

27-20

27-11

26-92

26-73

26-55

13-07

20-60 

21-40

22-00

22-05

21-90

21-75

21-60

19-73

25-20

26-90

26-90

2G-68

. 26-49

26-27

Correction 0

°C.

 03

.no

 13

 23

 37

 51

 66

 05

. }q

 91

.07

 62

 86

1-10

 03 

 08

 13

 23

 54

 68 '

 05 

 11

 17

 31

 50

 70

 89

 02 

 07

'12

 23

 54

 69

 04 

 11

 19

 32

 54

 75

 95

Correction h.

g. cnl.

19-9

16-7

15-5

21-1

17-7

20-4

h.

g. cal.

307 '314

316

01 Q

318

01 Q

318

182 

296

300

224 

259

266

9(»Q

268

268

270-

QMC

336

338

339

339

263

9Q7

324

330

330

330

330

235

9QT

320

326

326

327

326

Liquid.

\

£ 317-9 .

Immersion

Solid.

\

S 301-0

Solid.

\

S 268-2

Liquid.

\

> 338-8

Immersion

Liquid.

\

£ 330-3

Immersion

Liquid.

,

( 326-6

For brevity the last observations have been averaged per three minutes, and under li the mean for the last 11 minutes is usually given.

Thus in Series I the difference of temperature from top to bottom of 

the crucible is as large as 61° at 1200°, but falls off pretty regularly to 

6° at 829°. In Series II the corresponding mean difference is about.25° 

at 13000, 20o at 12000, 140 at HOOo and lOOOo, and 10° at 90QO and 

800°. The error thus involved can not be greater-than 2 per cent in 

.the extreme case; but since the distribution of temperatures is actually 

measured, the error is .probably negligible except at very high temperatures. I was inclined to infer that the greater constancy of the solid 

distribution as compared with the liquid was due to better conductivity 

in the former case (solid); but it may result as an equalizing effect of 

the tube, PI. VII, Fig. 3.

Considering the observational work as whole, the data are quite satisfactory, seeing that an error of-^-o 0. in the initial temperature of the
U. S. GEOLOGICAL SURVEY BULLETIN NO. 103 PL. VIII

400

300 §

400

300

200 EOO

100 100

<£ 1000'

RELATION OF THERMAL CAPACITY (SOLID AND LIQUID) TO TEMPERATURE (°C.). SERIES I.
BARUS.] THERMAL CAPACITY OF DIABASE. 53

calorimeter must vitiate the result as far as at least \ per cent. Hence 

the great care taken in finding this temperature. It is probable, how-' 

ever, that the real source of error is accidental and is encountered when 

the body falls out of the furnace into the water, particularly during 

the latter phase. Splashing, generation of steam, etc., then involve 

actual losses which can not be accounted for.

INFERENCES.

f>l. .'Digest and charts. In Tables 18 and 19 I have summarized the 

chief data on a scale of temperature. The results are graphically given 

in the charts, Pis. VIII and IX, in which thermal capacity in gramme 

calories is constructed as a function of temperature. Straight lines are 

drawn through the points, showing the mean specific heats for the intervals of observation, solid and liquid. The letter a marks the region 

of fusion.

It will be seen that both in the cases of PL VIII and PI. IX the solid 

points lie on lines which, if-reasonably curved, would be nicely tangent 

to an initial specific heat of about .2 at 0° C. The grouping, in other 

words, is so thoroughly regular as quite to exclude the probability of any 

anomalous feature in the observed or the unobserved parts of the locus. 

In both charts the solid point near a alone lies, markedly above the 

corresponding curve; but inasmuch as in my former work I found 

solidification to set in at 1,100° it is altogether probable that the occurrence. at 1,170° is incipient fusion.

TABLE 18. Thermal capacity of diabase. Series!. Digest.

Mean specific heat, liquid, 1200° to 1400°, -350. 

Mean specific heat, solid, 800° to 1100°, -304. 

Latent heat of fusion, at 1200°, 24ecal ; at 1100°, ICs 1 .

Solid.

Temperature. -

829

880

1001

1025

1078

*10UO

Thermal

capacity.

191

204

242

253

203

311

Liquid.

Temperature.

3274

1306

1337

1307

1378

Thermal

capacity.

358

304

373

370

385

* Incipient fusion? Tube sustained in the crucible.
54 FUSION AND PRESSURE. [BULL. 103. 

TABLE 19. Thermal edacity of diabase. Series II. Digest.

Mean specific beat, solid, 800° to 1100°, -290 

Mean specific heat, liquid, 1100° to 1400°, -360. 

Latent heat of fusion, 1200°, 246"'; at 1100°, 16s"1 .

Solid.

Temperature.

°C

781

873

948

993

1096

*1171

Thermal

capacity.

gcal.

180

202

227

238

268

302

Liquid.

Temperature.

»c.

1166

1194

1197

1215

1218

1248

1251

1251

* 1334

1352

Thermal

capacity.

gcal.

309

318

318

327

330

339

340

342

377

367

*Probably incipient fusion at the base of crucible (1177°).

Quite the same regularity is observable in the liquid loci, remembering that in PI. VIII only a single datum was taken for temperature, and 

that in PI. IX the high-temperature discrepancies above 1300° are 

within the range given in § 50, and due to distribution of temperature. 

, 52. Specific heat. As regards the mean specific heat between 800° 

and 1000°, in Tables 18 an,d 19, it will be seen that the intermediate 

datum (-304+'290)/2 would satisfy both groups of points about equally 

well. A tracing of one group of points nearly covers the other, while 

it is to be remembered that the true locus must be slightly curved. 

The same remarks may be made for the liquid state. I have discarded 

elaborate modes of reduction, since the equation of the locus would be 

arbitrary, and since the values for specific heat are of no immediate 

bearing on the present inquiry.

53. Hysteresis. Recurring to the suggestion of the preceding paragraph, it appears, since in my volume experiments I was able to cool 

down the rock to 1095° before solidification definitely set in, whereas, 

now, evidences for fusion do not occur before 1170° (at a, Pis. VIII and 

IX) that rock fusion must be accompanied by hysteresis 1 of the same 

nature as that which I observed with naphthaline, § 37. The magnitude 

of the lag is apparently 70°, and its pressure equivalent may be estimated as 500 atmospheres.

54. Latent heat. In virtue of the fact that the upper end of the solid 

locus can be carried so near the beginning of the liquid locus, the datura 

for latent heat is determinable with some accuracy. A difficulty, however, presents itself in the determination of the true melting point, a 

datum which can only be sharply defined while the temperature of the 

crucible is quite constant throughout. I, therefore, state the conditions 

at 1200° and at 1100°, where the latent heats would be 24 and 16 

gramme calories respectively, in both of the independent constructions 

of PI. VIII and PJ. IX. This coincidence is in a measure accidental.

 Am. Journal, XLII, p. 140, 1891.
U. S. GEOLOGICAL SURVEY

400

BULLETIN NO. 103 PL."IX

400

300 r^i 300

200.

a

ZOO

100 100

500 1000° 1500

RELATION OF THERMAL CAPACITY (SOLID AND LIQUID) TO TEMPERATURE (°C.(. SERIES
BAKUS.] MELTING POINT AND PRESSURE. 55

It may be noticed that a transitional temperature surprisingly near 

the region of fusion is apparently indicated.

55. The relation of melting point to. pressure. Tha first and second 

laws of thermodynamics lead to the equivalent of James Thomson's fusion equation, which in the notation of Clausius1 is

dT Tff-T

where Tis the absolute melting point, a r the difference of specific 

volumes solid and liquid at.27, r 1 the latent heat of fusion, and E Joule's 

equivalent. Combining the present series, J, with the former series, III, 

of volume measurements,2 1 obtain at 1200°, since T= 1470°, a r = 

 0394/2-72 (where 2-72 is the density of the solid magma at zero) and 

r' = 24,

and at 1100°, since T=:1370°, a-r = -0385/2-72, and r' = 16,

 (<*) =-029.

VWnoo.

Similarly combining the present series, IT, with the former series of volume measurements,3 IT7, at 1200°, since a r -0352/2-72 and r' = 24,

and at 1100°, since a r = -0341/2-72 and r'= 16

Hence the probable silicate value of dT/dp may be taken as -025, and 

falls nicely within the margin (-020 to -036) of corresponding data for 

organic substances (wax, spermaceti, paraffin, naphthaline, thymol). 

I may therefore justifiably infer that the relation of melting point to 

pressure, in case of the normal type of fusion, is nearly constant, irrespective of the substance operated on, and in spite of enormous differences of thermal expansibility and (probably) of compressibility. And 

in the measure in which this is true in passing from carbon compound 

to the thoroughly different silicon compound, it is more probably true 

for the same substance changed only as to pressure and temperature. 

In other words the relation of melting point to pressure is presumably 

linear.4

1 Clausius: Wiirmetheorie, I, p. 172, 1876. This is frequently called Clapeyron's equation.

2 Chapter it, §34. . 

» Chapter it, § 35.

4 See my work on the continuity of solid and liquid (Am. Journ. Sci., Vol. xlii, p. 144, 1891), iu which 

these relations are tested for naphthaline within an interval of 2,000 atmospheres.

INDEX.

Antoine, equation of.........

Apparatus for ebullition.....

Apparatus for fusion ........

Apparatus for calorimotry....

Basalt, specific heat of.......

 Bertram!, equation of.........

Boiling crucible..............

Boiling points, apparatus for

mercury..................

sulphur..................

Cadmium...:.............

zinc..................................

bismuth..............................

equations for ........................

graphically compared ................

Boiling point, criterion ..................

Boiling points of Carnelloy and Williams. 

Boiling tube.............................

Bismuth, boiling points of...............

Cadmium, boiling points of..............

Calorimeter..............................

Calorimetry, apparatus for ..............

method of............................

Caruelley and Williams on ebullition ....

Cells, standard...........................

Constants for vapor tensions ............

Clapoyron's equation.....................

Contraction (see Expansion) .............

Criterion for boiling points..............

Criterion for melting point..............

Critical temperature, lower..............

Cyclic fusion ............................

Data for expansion of diabase ...........

Diabase, for fusions......................

data for expansion of ................

specific heat of.......................

latent heat of........................

fusion and pressures for .............

Dilatational strain in glass ..............

Dupr6, equation of........................

Equations for vapor tension .............

Expansion of fusion tube................

Expansion of diabase, data for ... .37,38, 39,

Flotation of magmas.....................

Furnace for calorimetry .................

Furnace for volutnetry...................

Fusion, apparatus for....................

Fusion under pressure....!..............

Fusion and freezing alternating..........

Paga 

21

' .12,13

27, ?8

46

45

21,24 

13

12.13 

16

18

19

19,27

20

21

23

21

23

12

20

19

48

40

48

23

28

22

55

21 

54 

43 

42

37-41

25, 46

37-41

54

54

55

38

21

21

41

40,41

41

45

29

27

44

42

	Page. 

Fusion changes density of rocks......... 26

Fusion changes polymerism............ 20

Fusion tube.............................. 30

fusion volumetry, measurement of...... 33

computations in. .................... 34

errors of.............................. 35

Galvanometer (see Torsion galvanometer) .............................. u

Groshaus, hypothesis of................. U, 23

Hysteresis in fusions .................... 54

Kahlbauin on vapor tension.............. 17

King, Clarence, suggestions of .......... 9,25

Laws of vapor tension ................... 21

Latent heat of diabase ................... 54

Le Chatclier, pyrometer of............... ] 2

Magmas, polymerism of.................. 25

Melting point and pressure .............. 44

Melting point criterion .................. 54

Melting point and pressure for diabase .. ' 55

Meniscus in fusion tube.................. 36

Mercury, boiling points of............... 10

Micrometer, vertical..................... 31,37

Niess on rock fusion..................... 25

Polymerism in magmas.................. 25

Platinum, thermal capacity of ........... 47

Pyrometer, tests for ..................... 12,20

Kamsay and Young on vapor tension .... 17

Kesistance (electric) of magmas.......... 33

Roberts-Aiistin, on calorimetry.......... 45

Eiicker (see Koberts-Austin).............

Sight tubes .............................. 31

Specific heat of diabase .................. 54

Sulphur, boiling points of................ 18

Telephone registration................... 32

Thermocouple.........................16, 27, 30,40

Thermal capacity, chart for .............. 53

Of basalt ............................. 46

Of platinum.......................... 46

Of diabase.................. 49, 50,51,52,53, 54

Thomson J. J., equations of.............. 24,21

Thymol, volumetry of.................... 43

Torsion, galvanometer ................... 14

Tubes for, sight.......................... 31

Tube for fusions ......................... 30

Vapor tension, contents of................ 22

(See Boiling point).................... 21

Viscous yielding of platinum ....../..... 36

Zinc, boiling points of.................... 19.27

Zirkel, on rock fusion.................... 26

57