bluuebunny/crossref_metadata_2025 huggingface dataset:
On some Gasteropoda from the Silurian Rocks of Llangadock (Caermarthenshire)
Authors: Donald Jane
Published: October 2009

P
rof
. G
room
has sent me some pieces of rock of Silurian age, from Llangadock, containing a number of gasteropoda. These fossils occur almost entirely in the state of internal and external moulds. The former rarely show much structure, but by pressing wax into the latter the original form and ornamentation of the shells are frequently reproduced, in such a manner as to give a tolerably-good idea of the original. By this means I have been able to make out ten distinct forms, which are referable to seven different genera, but only seven are sufficiently well preserved to be specifically determined with any degree of certainty. They may be enumerated thus:—

Plethospira [Ulrichospira] similis
, sp. nov.

Bembexia (?) Groomii
, sp. nov.

Bemhexia (?)
sp. nov.

Bembexia (?) Lloydii
(Sow).

Murchisonia [Goniostropha] Cambria
, sp. nov.

Murchisonia [Cyrtostropha] torquota (?)
M'Coy.

Loxonema sinuosum (?)
Sow.

Loxonema Grindrodii (?)
Don.

Gyronema Octavia
(d'Orb.).

Polytropina globosa
(Schloth.)

Two small external moulds from the Upper Ludlow Beds, of which the wax-impressions bear some resemblance to
Cyrtostropha
torquata
(M'Coy) are too imperfect for certain identification. The same may be said of the much-worn internal mould from the Wenlock Beds, which possibly represents
Loxonema sinuosum
(Sow.). Besides these doubtful ones, there are three other species from Llangadock which have been previously described by other palæontologists, namely,
Bembexia(?) Lloydii
(Sow.),
Gyronema Octavia
(d'Org.), and
Polytropina globosa
(Schloth.). They all have a wide range, and cannot be considered characteristic of any particular horizon.
Cyronema Octavia
(d'Org.) is by
The Relations of the Eocene and Cretaceous Systems in the Esna-Aswan Reach of the Nile Valley
Authors: Beadnell Hugh John Llewellyn
Published: October 2009

I
n
the autumn of 1904 I had occasional opportunities of examining the desert-margins on both sides of the Nile Valley, between Aswan and Esna. The geological information hitherto published on this part of Egypt is so scanty that no apology is needed for putting on record the following observations, which, although disconnected, have an important bearing on a somewhat vexed question of Egyptian geology, namely, the mutual relations of the Cretaceous and Eocene systems.

(1) The Kom-Ombo Plain.

From Aswan to Darau the valley is comparatively narrow. Immediately north of the latter place it opens out, from a narrow gorge closed in by sandstone-hills, to a broad plain bounded by an undulating sandstone-desert on the west side, and by the ordinary sandstone-hills on the east: the latter running round in a wide curve, and not approaching the river until Jebel Silsila, 30 kilometres (sixteen and a half miles) farther north, is reached. In the centre of this area, on the eastern bank of the river, is the temple of Kom Ombo, from which the plain takes its name.

As has long been recognized, the plain is superficially an extensive alluvial deposit; in addition to the sands and clays, with fluviatile shells and occasional mammalian bones, bands of tufaceous limestone are met with in the neighhourhood of Fatira. These deposits cannot be classed with the recent Nile alluvium, as they belong to the period of the great Pleistocene lakes of the Nile Valley, and have their surface some 25 metres (82 feet) above the
The Doncaster Earthquake of April 23rd, 1905
Authors: Davison Charles
Published: October 2009

I. Introduction

On April 13th, 1902, a slight earthquake occurred in the north of Lincolnshire. Its intensity was not more than 4, and the area disturbed by it included about 600 square miles. The shock was of the simplest character, lasting on an average for 4 seconds, and consisting of a single series of vibrations, which increased in intensity to a maximum and then died away. Though of little consequence when considered as an isolated event, the shock derives interest from its probable connection with the much stronger twin-earthquake which occurred in the same district three years later, on April 23rd, 1905.

On this day, there were two undoubted earthquakes, namely:—

(
a
)

About 1.30 a.m.

(
b
)

1.37 a.m. (principal earthquake).

In addition to these, several disturbances of uncertain seismic origin are reported:—

April 23rd, about 1.39 a.m.: Barton-on-Humber.—A very slight shock, similar to that of the principal earthquake, and accompanied by a sound like distant thunder.

April 23rd, about 2.5 a.m.: Farnsfield and Normanton-on-Trent.—A slight shock, without any attendant sound, was felt at these places, both of which are more than 15 miles from the principal epicentre.

At Farndon (near Newark) subterranean noises are said to have been heard on several occasions, especially on April 27th, at 11.30 p.m., and on April 29th, about midnight.

A slight shock was felt at Epworth, and a rumbling sound was heard at Norton. Epworth lies between the two portions of the isoseismal 7 of the
The Tarns of the Canton Ticino (Switzerland)
Authors: Garwood Edmund J.
Published: October 2009

I. Introduction

The study of lakes, so long neglected by geographers in the past, has of recent years received a great impetus from the investigations of Prof. Forel, M. Delebecque, Prof. Penck, and other workers on the Continent, and of Prof. Russell, Prof. Gilbert, and Prof. W. M. Davis in America; while in our own country, Dr. Mill, Dr. Marr, Sir John Murray, Mr. Pullar, and others have aroused our interest in this fascinating subject.

In his exhaustive ‘Handbook of Limnology,’ Prof. Forel remarks:— ‘Each lake is an organism in itself, each has its peculiarities, its special history in the past and in the present, each deserves a special description. Hence the charm and also the scientific value which attach to the study of lakes in general and to that of each lake in particular.’

Of all the numerous interesting branches of study connected with lakes, that of the origin of the hollow in which the lake occurs is the one that must especially appeal to the geologist; while of these hollows, those basins that are entirely surrounded by solid rock are certainly the most interesting and the most difficult to explain.

The theory, originally advanced by the late Sir Andrew Ramsay, and supported by Tyndall, Gastaldi, and de Mortillet, which would have us regard the majority of the large Alpine lakes as due to the direct erosive action of ice, has gradually given rise to a detailed consideration of the genesis of each individual lake.

At the present day
The Highest Silurian Rocks of the Ludlow District
Authors: Elles Gertrude L. , Slater I. L.
Published: October 2009

I. Introduction and Bibliography

The Ludlow district has been regarded as classic ground since the days of Murchison, and, although it has been much neglected by the geologists of more recent times, local collectors of fossils have placed in the Ludlow Museum a collection which is probably unsurpassed for its excellence in illustrating the geology of the neighbourhood.

Many papers were written upon the district by Murchison and others of his time; but, with the exception of Miss Wood's paper on the Lower Ludlow Shales, there has been no revision of its geology since their day: and we are of opinion that the area presents many features of interest, both structurally and otherwise, which can only be brought out by more recent methods of research.

In the Ludlow-Downtown district there exists an interesting series of rocks, limited by the Aymestry Limestone at their base and the Old Red Sandstone at their summit, and it is with these that the present paper deals. Lithologically, they present a varied series of sediments, ranging from limestones on the one hand, through calcareous flagstones and shales, to shallow-water sandstones on the other; and these lithological changes are associated with certain changes in the fauna.

Palæontologically, these rocks are characterized by the presence of Eurypteridæ, which, although rare in the lower beds, gradually increase in importance until they attain their maximum development in the beds immediately underlying the Old Red Sandstone. The rich brachiopod-fauna characteristic of the lower beds dwindles and almost dies out with
On the Igneous and Associated Sedimentary Rocks of Liangynog (Caermarthenshire)
Authors: Cantrill Thomas Crosbee , Thomas Herbert Henry
Published: October 2009

I. Introduction

In the neighbourhood of the village of Llangynog, some 6 miles south-west of the town of Caermarthen, an elevated tract of ground lying between the River Towy on the east and the Cywyn on the west, presents features of especial interest in that it contains several small masses of igneous rocks among the Ordovician sediments. In the re-mapping on the 6-inch scale of the South Wales Coalfield and the ground adjacent thereto, it fell to us to re-examine this district. In memoirs necessarily devoted chiefly to a description of the Coal-field, it is not possible to enter into such detail concerning the petrology and stratigraphy of these older rocks as they seem to deserve. We therefore sought the permission of the Director of the Geological Survey to lay before this Society the following particulars.

The district is comprised in the Old Series 1-inch Ordnance-map, Sheet 41; in the New Series 1-inch map, Sheet 229 (Caermarthen), and in the 6-inch maps, Caermarthenshire 38 S.E., 39 S.W., 45 N.E., and 46 N.W. It consists of an elevated plateau, which at Pen-y-Moelfre and Castell Cogan attains an altitude of 546 feet and 426 feet respectively; it is drained in part by several streams which flow southward into the estuaries of the Tâf and the Towy, and in part by streams flowing north-westward into the Cywyn, which itself falls into the Tâf.

The south-eastern part of the plateau is occupied by the red marls of the Lower Old Red Sandstone, the base
The Carboniferous Rocks at Rush (County Dublin)
Authors: Matley Charles Alfred , Vaughan Arthur
Published: October 2009

I. Introduction. [C. A. M.]

Although Carboniferous rocks form the rock-floor of the greater portion of the County of Dublin, they are so much concealed inland by Glacial Drift as to render their structure and relationships usually obscure. On the coast, however, they crop out in several very good sections, especially near Malahide, about 4 miles north of Dublin Bay, and at Rush, about 6 miles still farther north. The latter is the more extensive and interesting of these two.

From the shore south of Rush village, extending northward past Loughshinny to within a mile of Skerries—a distance in all of about 5 miles—the Lower Carboniferous rocks are splendidly exposed: the outcrops being only interrupted occasionally, where the shore is covered by sand, or the Glacial Drift descends to sea-level. At the suggestion of Mr. G. W. Lamplugh, F.R.S., and tempted by the interesting character of the rocks themselves, I was induced (during a temporary residence in Ireland) to make a detailed examination of these beds. In order to understand the coast-section in full detail, a horizontal section of the beds, as shown in the cliffs and along the rocky shore, has been prepared for the whole distance on the scale of 1 inch to 10 feet. As, however, fossils have up to the present been collected only from the rocks near Rush, that is to say at the southern end of the line of section, the present communication will be restricted to that part of the area; but account
On the Carboniferous Limestone (Avonian) of the Mendip Area (Somerset), with especial reference to the Palæontological Sequence
Authors: Sibly Thomas Franklin
Published: October 2009

I. Introduction.

This paper contains the results of a detailed examination of the Carboniferous Limestone in the Mendip area.

The object of my work has been the complete investigation of the faunal sequence in the Carboniferous-Limestone Series, following on the lines laid down by Dr. Arthur Vaughan, in his great paper on ‘The Palæontological Sequence in the Carboniferous Limestone of the Bristol Area.’ Detailed work in the Mendips has shown that the system of zones and subzones, established by Dr. Vaughan in the Bristol sequence, requires only very slight modification to co-ordinate accurately the faunal sequence in the Mendip area. The correlation of the Mendip and Bristol areas is treated fully in the present paper, my comparison being based on Dr. Vaughan's paper, to which I make frequent reference.

I am indebted to Mr. H. B. Woodward's Geological Survey-memoir on ‘The Geology of East Somerset & the Bristol Coalfields,’ published in 1876, and to a paper by Prof. C. Lloyd Morgan, entitled ‘Mendip Notes,’ published in the Proceedings of the Bristol Naturalists’ Society, for much valuable information and guidance. To my recent paper on ‘The Carboniferous Limestone of Burrington Combe,’ which deals fully with the Burrington section, I refer frequently.

The Carboniferous Limestone presents more or less complex structural features in several parts of the Mendip area, and it is to be hoped that the application of palæontological study to these problems will furnish correct solutions. The time at my disposal has not permitted me to pay much attention to
The Geology of Dunedin, (New Zealand)
Authors: Marshall Patrick
Published: October 2009

I. Introduction, and Description of the Topography of the Area.

The eastern coast of the South Island of New Zealand has two projecting points consisting of volcanic rocks of Kainozoic age. These igneous masses constitute Banks Peninsula and the Otago Peninsula. Except in regard to their physiographical nature, neither of these areas has been submitted to accurate geological examination, although enough work has been done to show that both of them offer a most interesting field for petrographical study.

The general structure of Banks Peninsula was studied by Sir Julius von Haast, who traced and described various crater-walls which were the boundaries of the foci of most intense volcanic activity. The structure of one of these—Lyttelton Harbour—was displayed with great clearness in the walls of the railway-tunnel that pierced it, and Sir Julius has given an accurate description of this.

Many of the rock-specimens collected during the tunnel-driving were described and figured by the officers of the French Campbell-Island Expedition. Other rock-specimens from the district have been described by Marshall, Speight, and Ulrich.

So far as its general structure is concerned, Otago Peninsula has received less notice, though brief descriptions have been given by Hutton, Hector, and Ulrich. More detailed work has been devoted to the Otago-Peninsula rocks, and some types were described by Hutton, and later, in a far more elaborate manner, by Ulrich. who was the first to recognize the specially-interesting series of alkaline rocks that occurs here.

In the present paper an attempt will be made to
The Chalk and Drift in Möen
Authors: Hill Edwin
Published: October 2009

The volume for 1899 of the Quarterly Journal of the Geological Society contained a paper by Prof. Bonney and myself on the ‘Relations of the Chalk & Drift in Möen and Rügen,’ in which we expressed the opinion that the existing dislocations of the Chalk had been produced before the advent of the Drift.

In 1904, there appeared a second edition of ‘Danmarks Geologi,’ by Prof. N. V. Ussing. This, on p. 89, mentions the phenomena of Möen, and some of the explanations of them put forward. Forchhammer, it says, assumed that they were results of plutonic forces: Johnstrup considered them to be caused by the thrust of the mighty inland ice-sheet which passed over Denmark : German writers more recently have explained them as consequences of widespread earth-movements, with or without ice-thrust. But there is no allusion to the view taken in our paper; therefore I think that it may be useful to publish the results of further study made by me in 1903, 1904, and 1905.

The problem of Möen is to account for the position of some isolated small portions of clay, seen here and there included in the Chalk along a range of chalk-cliffs some 4 miles long. The beds are much dislocated. Forchhammer, followed by Puggaard and Lyell, regarded the disturbances as subsequent to the Glacial deposits, and the Drift-inclusions as portions engulfed. Johnstrup, regarding the disturbances as due to thrust of the ice-sheet, considered the Drift-inclusions as introduced by the same agent. Prof. Ussing
Liassic Dentaliidæ
Authors: Richardson Linsdall
Published: October 2009

The Great Western Railway-line between Honeybourne and Cheltenham now (1906) nearing completion, necessitated the making of a considerable number of cuttings in the Lias, the zones exposed dating from
oxynoti
to
capricornus
inclusive. Among the fossils collected were many belonging to the family Dentaliidæ. The majority of the forms appeared to be new, and consequently a somewhat exhaustive investigation of the Liassic members of the family was imperative. In the course of these investigations, through the courtesy of the respective keepers, the specimens preserved in the Natural History Museum, the Museum of Practical Geology (Jermyn Street), the Geological Society's Museum (Burlington House), the Sedgwick Museum (Cambridge), and the Bath Museum, have been examined.

Occasionally some difficulty arises in distinguishing the tubes of certain tubicolous annelids of the genus
Ditrupa
from those of the Dentaliidæ; but, if the less regular character of the tubes does not suggest their true zoological position, a microscopic investigation will in most cases soon elucidate matters. The shells of scaphopods are of course open at both ends, which is not the case with those of the Serpulidæ.

It may be of interest to mention that the growth of the scaphopodshell is effected by means of successive increments at the anterior end, while contemporaneously the posterior end suffers by wear and absorption. The members of this class (Scaphopoda) are essentially marine organisms, and for the most part inhabit deep water, being embedded in the mud or sand with only the posterior end of the shell projecting above
The Tarannon Series of Tarannon
Authors: Wood Ethel M. R. , Shakespear G. A.
Published: October 2009

I. Introduction.

(A) Historical Review.

Stretching southward for 70 miles from the shores of the Irish Sea near Conway in North Wales, through Denbighshire and Montgomeryshire into the central parts of Radnorshire near Llanbister, there sweeps a continuous band of massive greywackés, flagstones, and shales, known to geologists as the Denbighshire Grits or Flags. This arenaceous formation is from 1000 to 3000 feet in thickness, and is acknowledged on all hands to be of Wenlock age.

Rising out from beneath the Denbighshire Grits, and intervening between them and the older rocks which are at present assigned to the Llandovery and Bala, there occurs a series of relatively shaly strata which are distinguished on the Geological-Survey maps by a special tint of purple, and are indicated upon the legends as ‘Tarannon Shales.’ They are laid down on the maps as forming a narrow belt, seldom exceeding a quarter of a mile in width and entering into all the sinuosities of the outcrop of the lower margin of the Denbighshire Grits.

Although these so-called ‘Tarannon’ Beds were not mapped as constituting a distinct formation until 1855, their peculiar mineral characters—‘fine, smooth, slaty strata, grey or light blue, occasionally slightly sandy, and alternating with purple bands’—had not escaped the attention of the earlier geological workers in Wales. As early as 1843 Sedgwick and Sailer had noticed in the Berwyn Hills certain ‘pale-coloured earthy slates’ which ‘seem to pass without a break into the overlying Denbigh Flagstone.’ From the fact that they were aluminous
On the Importance of
Halimeda
as a Reef-Forming Organism: with a Description of the
Halimeda
-Limestones of the New Hebrides
Authors: Chapman Frederick , B.E., B.Sc. Douglas Mawson
Published: October 2009

I. Occurrence and Conditions of Growth of Living
Halimeda

The importance of
Halimeda
as a reef-forming agent has, until of late years, been greatly overlooked. Many of the earlier records of the occurrence of calcareous seaweeds on coral-reefs were alluded to in a comprehensive manner, as Nullipores and
Lithothamnion
; and, although
Halimeda
was not mentioned, the above terms, convenient but often vague, undoubtedly included growths of that genus.

Prof. A. Agassiz has already recorded the fact that ‘immense masses of Nullipores (
Udotea
and
Halimeda
) . . . grow on the shallowest flats’ of the Florida reefs.

With regard to the habitat of
Halimeda
in the Laccadives, the following interesting note on
H. opuntia
, Lamx. forma
typica
, by Mr. J. Stanley Gardiner, has been published in a paper by Miss E. S. Barton (Mrs. Gepp):— ‘Rare everywhere on the Minikoi reef; but small masses may be found by searching under stones or in protected situations of the inner part of the reef, near the beach or boulder-zone. In lagoon, not found in currents, but very luxuriant in moderately-still water where it can find any stones to fix itself upon.’

From the dredging operations of Messrs. David, Halligan, & Finckh around the atoll of Funafuti we learn that
Halimeda
is found in the outer slope of the atoll, from a foot or so below sea-level down to about 45 fathoms.

In the dredgings across the lagoon at Funafuti the variety
macropus
occurred in all the samples, excepting No. 1 (half a mile
The Crag of Iceland: an Intercalation in the Basalt-Formation
Authors: Pjetuesson Helgi
Published: October 2009

The existence of fossiliferous deposits on the western coast of Tjörnes (Northern Iceland) has been known to science for nearly 160 years. They were first mentioned by the famous Egbert Olafsson in his book entitled ‘Enarrationes historicæ de Islandiæ Natura & Constitutione,’ etc., published at Copenhagen in 1749.

In 1871 the Danish conchologist O. A. L. Mörch published a paper ‘On the Mollusca of the Crag-formation of Iceland,’ wherein he enumerated 61 species of molluscs, and arrived at the conclusion that in the Crag-period the temperature of the northern coast of Iceland must have been much milder than now, ‘at least as at present on the west coast by Reikiavik’ [Reykjavik],
op. cit.
p. 394.

Some years later, Mr. J. Starkie Gardner collected 33 species of Pliocene molluscs in Iceland, which were studied by Gwyn Jeffreys and Searles V. Wood. In the opinion of Wood, the deposits in question cannot be younger than Middle Red Crag, while Jeffreys thinks that they are somewhat younger. Gardner himself is, however (Quart. Journ. Geol. Soc. vol. xli, 1885, p. 97), ‘inclined to assign a greater age to the deposit from its general appearance on the spot, than Dr. Gwyn Jeffreys may do, or even than Mr. Searles Wood.’

The most important paper in existence on the fauna of the Icelandic Crag dates from 1884, but only exists in a manuscript, which has been deposited in the archives of the Geological Museum of Copenhagen. It is written by C. M. Poulsen, and is in
On the Upper Carboniferous Rocks of West Devon and North Cornwall
Authors: Arber E. A. Newell
Published: October 2009

I. Introduction.

For some years past my attention has been directed to a study of the Upper Carboniferous rocks of Devon and Cornwall. The main object of enquiry has been to ascertain as much as possible of the fossil plant-remains, more especially with a view to determining the horizons to which they belong.

Some of the results attained have been already published. Inthe present, communication an account is given of more recent and concluding observations. It has been thought well to add some brief reference to the main conclusions which have appeared else-where, in order to treat of the whole area under discussion in as connected a manner as possible.

In a previous paper 1 a description was given of the fossil plants obtained from the district around Bideford, the geology of which is well known and has been repeatedly described. 2 The present paper is, in the main, concerned with a much wider area. As the result of a close search for plant-remains in the Upper Carboniferous rocks lying to the south and west of Bideford, and extending into North Cornwall, other discoveries have been made incidental to the progress of the main line of enquiry.

These, although strictly lying beyond my province, I have felt it my duty to record,if only imperfectly, since the district has not hitherto been examined. Thus, in addition to the plant-evidence, I have endeavoured to add some account of the physical characters of the beds, as well as of the invertebrate fossils which
On the Skull and greater Portion of the Skeleton of
Goniopholis crassidens
from the Wealden Shales of Atherfield (Isle of Wight)
Authors: Hooley Reginald Walter
Published: October 2009

I. History of The Descovery of The Specimen.

In the late autumn of 1904, at a place locally called ‘Tie Pits,’ near Atherfield Point (Isle of Wight), a large mass of the cliff, comprising many thousand tons of the Wealden Shales, subsided, pushing its foot across the beach, until below low-water line. As the sea washed away the base, the mass continued sinking, and fresh horizons were denuded. In 1905 a series of heavy ‘ground-seas’ cast up blocks of limestone and ironstone, containing crocodilebones, which were discovered on the sand, between high and low water marks. The skull came ashore in six pieces, and on as many different occasions.

Scutes and fragments of bones were constantly picked up. One block found by a local fisherman was ibrwarded to the Sedgwick Museum, at Cambridge. After correspondence with Mr. Henry Keeping, the well-known Curator, I was put in communication with Prof. T. McK. Hughes, F.R.S., who, with great liberality and courtesy, wrote that in ' the interest of scientific progress' he thought that their block should be handed over to me, and this was accordingly done.

The collection of the skull, etc. would have been impossible, but for the aid of Mr. Walter White, the coxswain of the Atherfield lifeboat, who obtained the separate portions by visiting the beach at every tide. The horizon whence the specimen was derived is 80 to 90 feet below the top of the Wealden Shales.

II. History of The British Goniopholid
Æ
.

The genus.
The Titaniferous Basalts of the Western Mediterranean: A Preliminary Notice
Authors: Washington Henry S.
Published: October 2009

In the summer and autumn of 1905 the volcanic districts of Catalonia, Sardinia, Pantelleria, and Linosa were visited by me, and their rocks collected under the auspices of, and with the aid of a grant from, the Carnegie Institution of Washington. During the past year, the abundant and representative material thus brought together has been the object of microscopical and chemical study, which is still in progress. The final results of these investigations are to appear elsewhere, as separate papers dealing with the rocks of the several districts; but some observations and conclusions of a general character appear to be sufficiently well-established, and of enough interest, to justify their publication in advance of the more detailed descriptions.

It is the object of the present communication, which I have the honour of laying before the Society, to call the attention of petrologists to the existence, in the Western Mediterranean Basin, of a hitherto unrecognized petrographic province, or comagmatic region, to adopt a term used by me elsewhere, one of the most salient characters of which is the presence of salfemanes (basalts) that contain remarkably-high amounts of titanium. The data available at present are far from complete, as only a small proportion of the numerous rock-types have been analysed: the analyses so far made by me being mostly of basalts (salfemanes), with fewer of the more salic rocks. Furthermore, there are several gaps in the comagmatic zone, at localities which I was unable to visit, and the rocks of which are still
On Changes of Physical Constants which take place in certain Minerals and Igneous Rocks, on the Passage from the Crystalline to the Glassy State; with a short Note on Eutectic Mixtures
Authors: Douglas James Archibald
Published: October 2009

The effect of high temperatures on minerals and igneous rocks has long been a subject of geological research. De Saussure, in 1779, was the first to remark the fact that igneous rocks diminished in density on fusion, and became converted into a glassy substance. Further investigations as to these phenomena were made by Dolomieu in 1788, Sir James Hall in 1790, Magnus in 1831, and Bischof in 1841. The work of these early observers inspired Delesse in 1846 to publish an important paper on the glasses formed by the fusion of igneous rocks. This paper gives a good idea of the methods employed, at a time when electrical heating was an unknown factor in scientific research. With the improved appliances of modern science, the number of investigators has so greatly increased that it is only possible to mention the more recent researches of Barus, Dœlter, Joly, Teall, Cusack, Bakhuis Roozeboom, Vogt, Åkerman, Allen, and Day.

At the present time, every well-appointed laboratory has its electrical installation, and high temperatures may thereby be easily attained. As I had a strong current at my disposal. Prof. Sollas suggested that I should melt certain minerals and igneous rocks by means of a simple platinum-resistance, and endeavour to redetermine the change of specific gravity which accompanies their fusion.

In the following paper I have given a brief account of some experiments on the fusion of igneous rocks, and the determination of their specific gravities in the glassy state; I have also added a few
On the Xerophytic Characters of certain Coal-plants, and a Suggested Origin of Coal-Beds
Authors: Henslow George
Published: October 2009

In endeavouring to interpret the nature of the coal-flora, we can only do so by comparing the various members of it with living plants; and, when this is done, their anatomical structures exhibit both hygrophytic as well as strong xerophytic characters in various genera. It has been generally supposed that the whole of the coal-flora consisted of marsh-herbs and trees. They all, therefore, ought to reveal hygrophytic characters, such as the following, which are nearly always to be found in living aquatic plants:—

If they be hydrophytes, then there will be, as a rule, no axial root. An illustration of the basal part of a stem of a Calamite, in Prof. Seward's work on ‘Fossil Plants’ vol. i (1898) p. 343, affords an excellent example of an aquatic plant. The arrest of the axial root and lower extremity of the stem is probably due to the absence of oxygen in the mud necessary for respiration, and the presence of poisonous gases, such as marsh-gas. A similar form of stem with adventitious roots is well seen in our common
Œnanthe Phellandrium
. This is, in fact, characteristic of Dicotyledonous aquatic plants and of all Monocotyledons. The form of the stem is an inverted cone, having adventitious roots, forming the so-called ‘prop-roots’ of mangroves (and of the terrestrial
Pandanus
or screw-pine, maize, and palms, among Monocotyledons); or else the presence of ‘pneumatophores’ is the most characteristic morphological feature of water- or swamp-plants.

With regard to the internal tissues, there will be an abundance
On the Southern Origin attributed to the Northern Zone in the Savoy and Swiss Alps
Authors: Bonney T. G.
Published: October 2009

In two most valuable and interesting papers contributed to our Journal, Prof. Sollas has described the results of experiments made with cobbler's wax, and designed to illustrate the internal movement of a viscous fluid or very plastic solid under the action of gravitation, which was set up originally by the wedge-like form of the mass and continued by adding new layers, more or less similarly shaped, of the same material. Complications were introduced, as described in the second paper, by attaching to the floor of the trough used for the experiment, first one, then two, mound-like obstacles over which material, once near its head, was forced by the pressure of that subsequently added: the result being the formation in the older layers of some remarkable folds, and even dislocations, especially in front of the second obstacle

These experiments, as Prof. Sollas pointed out in his first paper, throw much light on the movements of glaciers; but whether they give any real support, as is suggested in the second paper, to Prof. Lugeon's explanation of the flexures in the Chablais district and its continuation across the Rhone, is, in my opinion, very doubtful. This hypothesis may be briefly stated in the following terms:—On the northern side of the great crystalline massif, the crest of which forms the watershed of the Pennine-Lepontine Alps, is a second one—that of the Bernese Oberland. Its eastern end, before reaching the Rhine, disappears beneath a thick covering of Secondary and early Tertiary rocks.Its western end
The Geology of the Oban Hills (Southern Nigeria)
Authors: Parkinson John
Published: October 2009

The country worked over comprises some 1800 square miles adjacent to the Kamerun frontier, lying in the form of an ellipse, with its major axis running north and south, bounded respectively by the Cross River and the swamps east of Calabar. (see map. p. 314).

I arrive at the following conclusions :—

(1)

A study of the Eastern Province of Southern Nigeria shows the Oban Hills to be part of an extensive spur or inlier of crystal-line rocks, surrounded in British territory by Cretaceous and later sediments.

(2)

The crystalline rocks are broadly divided into two groups— the one characterized by the presence, the other by the absence of foliation.

(3)

The former consists in part of acid orthogneisses, which tend to lose their foliation and pass into granites, and when coarsely crystalline they have a pegmatoidal habit.

The commonest rock of the series is a fine-grained biotite-gneiss, but many varieties are found, and it is considered that these are the members of a differentiated magma, the various products of which took up their present positions at different times : that is, they differ slightly in age. Mica and less frequently hornblende-schists, together with sphene-sehists and rare sillimanite-gneisses (Awöfong), occur throughout the district, and it is contended that these rocks are older than the gneisses.

At Abuton (Kwa River) a garnet-tourmaline-orthogneiss is associated with a fine-grained mica-schist, so closely as to produce a banded composite gneiss by a process, apparently
The Constitution of the Interior of the Earth, as revealed by Earthquakes: (Second Communication). Some New Light on the Origin of the Oceans
Authors: Oldham Richard Dixon
Published: October 2009

The origin of the great oceanic basins has been the subject of numerous speculations, more or less plausible, but none convincing: for the reason that we have no knowledge as to whether these depressions are mere surface-phenomena, or whether they are accompanied by, and related to, differences in the constitution of the interior of the earth beneath them. It is known that the attraction of gravity is, as a rule, greater at island-stations than on the continents, and that the plumb-line at coast-stations is frequently deflected towards the sea; but these facts do not help, for they are easily explicable by differences which may be regarded as superficial, seeing that they need not extend to a depth of even as much as one hundredth of the earth's radius. As regards greater depths, mathematical deductions can help us but little, for any deductions drawn in this way are subject to the logical objection that, while showing the possibility of one explanation of known facts, they do not exclude the possibility of some other. Direct or positive evidence is therefore desirable, and this I propose to offer: not indeed amounting to proof, but still strong enough to merit serious consideration, that the ocean-basins of the Northern Atlantic and Northern Pacific are not mere surface-departures from the perfect spheroid, but are accompanied by differences in the constitution of the matter underlying them, which extend to a considerable portion of the whole radius of the earth.

In a previous communication I showed that the
Appendix I.—On the Correlation of the Bath-Doulting Strata with those of Dorset
Authors: Buckman S. S.
Published: October 2009

Mr. Richardson has asked me to say a few words about the correlation of the strata described by him with the Upper Inferior Oolite + the Fullers′-Earth rocks of Dorset. As I have had the opportunity of reading his careful exposition in manuscript, I very gladly accede to his wish.

To make the subject clear I append the following Table (V, p. 425), giving the generalized sequence of the strata in North and South Dorset and correlating therewith the Bath-Doulting strata.

About this Table I would make the following remarks:—There are three horizons which can be correlated without much difficulty, namely: (1) The Fullers′-Earth Rock of Dorset and the Fullers′ Earth of Midford; (2) Beds with stout-whorled
Parkinsonia
of South Dorset and the Anabacia-Limestones of Bath-Doulting; (3) The Building-Stone of Sherborne and the Upper
Trigonia
-Grit of the Cotteswolds, which Mr. Richardson has followed into the Bath-Doulting district.

As to other strata, the Lower Fullers' Earth and the
Fusca
-Beds of North Dorset are, I fancy, entirely unrepresented in the Bath-Doulting district, where, too, there is but a trace of the strata of the
zigzag
hemera; so that in this North Somerset district, as I interpret it, the strata of
subcontracti
hemera rest non-sequentially in most eases on strata of pre-
zigzag
date.

These strata are what Mr. Richardson has called the
Anabacia
-Limestones. There is little to represent them in North Dorset; but in South Dorset there are some feet of limestone earlier than
zigzag
and later than
Truellii
, characterized by certain stout-whorled
Appendix II.—Remarks on the Brachiopoda from the Fullers′ Earth
Authors: Richardson Linsdall , Walker John Francis
Published: October 2009

The following species of brachiopods have been recorded from the ullers Earth of England: the spemes that occur in the district described in the foregoing paper being denoted by an asterisk.

Diagnosis.—Shell globose, wider than long, apical angle acute, margins of the shell rounded and somewhat fimbriated. The shell is coarsely-ribbed, the spaces between the ribs being imbricated, and the ribs are ornamented with irregularly-distributed spines. The ventral or pedicle-valve has its greatest thickness near the centre, sloping towards the anterior margin, where there is a shallow central fold which occupies about a third of the width of the shell. The beak is short, strongly incurred, and touches the umbo of the dorsal or smaller valve. The dorsal valve is moderately convex, thickest in the centre, and slightly truncated at the anterior margin, which is fimbriated.

Remarks.—This variety of
Acanthothyris
is not well-defined, but can be separated from
A. spinosa

Specimens from Midford differ somewhat from that figured, which came from Doulting, in having a few more ribs, so that in this respect the species is a little variable.

The fossil is very characteristic of the lower portion of the Fullers' Earth of the Bath-Doulting district, and has been found at the Farmcombe and Doulting-Bridge Quarries; between Doulting and Cheylinch; in the railway- and road-cuttings, and at the Fullers'-Earth Works, Midford; also at the quarry situated about a mile east of Paulton Church.

Diagnosis.—Shell rhomboidal, longer than wide, the greatest width being near the centre of the shell, whence the
On a Marine Fauna in the Basement-Beds of the Bristol Coalfield
Authors: Bolton Herbert
Published: October 2009

The failure to discover anything in the nature of a definite fauna in the Bristol Coalfield has long been a well-known and somewhat remarkable fact. Isolated and rare fossils have been occasionally discovered, but the list of genera and species hitherto recorded is a short one, and not sufficiently representative to be in any sense distinctive, either of any horizon, or of the coalfield as a whole. Thirty years ago, W. W. Stoddart,1 who had a wide knowledge of the Coal-Measures, stated that he had not met with animal-remains of any description. Still earlier, however, John Morris had recorded the occurrence of bivalve mollusca (
Anthracoptera?
) in the coal-shale at Twerton, near Bath; while, from bituminous shale at Nailsea, he obtained
Estheria striata
, var.
Beinertiana
, and an imperfect cast of
Beyrichia arcuata
(?). From the roof of the White Seam of Youngwood Pit, Nailsea, were obtained
Kirkbya costata
and a species of
Cythere
. In shale at 200 feet above the White Seam was observed an ostracod, closely resembling
Cythere fabulina
. The same note states that Mr. J. McMurtrie, F.G.S., recorded the occurrence at Camerton of several specimens of bivalve shells (
Anthracosia?
) and two specimens of
Limulus
, all of which had been found by Mr. E. Feare. The
Limulus
in question was, I believe,
Prestwichia rotundata
.

Some years ago two other specimens of the same species were found: one at Radstock, which is now in the possession of Mr. J. McMurtrie; and the other at Clandown Colliery, which is in the possession
The Faunal Succession in the Carboniferous Limestone (Upper Avonian) of the Midland Area [North Derbyshire and North Staffordshire]
Authors: Sibly Thomas Franklin
Published: October 2009

1. I
ntroduction
.

The area of Avonian rocks with which this paper deals, and which I term the Midland Area, includes the large, irregularly-shaped periclinal mass of Carboniferous Limestone, forming the southern termination of the Pennine anticline, south of the Peak, and comprises also a few small inliers adjacent to this main outcrop. (See map, fig. 1, p. 35.) The main part of this area is included in Derbyshire, but a small, south-western portion lies in Staffordshire.

In the Geological-Survey Memoir on North Derbyshire, the Carboniferous-Limestone succession of this area, as shown by the extensive section between Buxton and Monsal Dale, is briefly described; details of a few other sections are given; and the nature of the junction between the Carboniferous Limestone and the overlying shales, as seen at various points, is discussed. An account of the elementary tectonics of the area, and of the general features of the Carboniferous Limestone, is contained in a paper by Mr. H. H. Arnold-Bemrose, entitled ‘A Sketch of the Geology of the Lower Carboniferous Rocks of Derbyshire,’ published in the Proceedings of the Geologis'ts’ Association, vol. xvi (1899–1900) p. 165. Details of a new sections in the area are given in papers by Mr. Arnold-Bemrose and by Dr. Wheelton Hind, published in the Quarterly Journal of the Geological Society and elsewhere: I refer to these in the course of the present paper.

The tectonic structure of this area has not yet been adequately investigated. However, the detailed mapping of the igneous rocks associated with
Chronology of the Glacial Epoch in North America
Authors: Wright George Frederick
Published: October 2009

In the case of Plum Creek, Lorain County (Ohio), the study of the activity of the stream and of the amount of work which it has done since a certain stage of the Glacial Epoch, has yielded important results. This stream began the erosion of its trough when the temporary lake, held up in front of the ice, was maintained for a considerable period at the level of its Fort-Wayne outlet; it has never had anything more resistant than Till to act upon. From a given section, 5000 feet long, it has excavated 34,000,000 cubic feet of Boulder-Clay, removing it from exposed banks 1600 feet long. Twelve years' erosion of a 500-foot length of a part of the trough of the stream under observation, and from banks 1000 feet long, gives a rate of 8450 cubic feet per annum. Therefore, the removal of 34,000,000 cubic feet from the 5000-foot section would give a period of 2505 years. Considerations tending to lengthen the estimate are the former forestation of the area and the increased gradient in the artificial cut-off. Those tending to shorten the estimate are the present wider flood-plain, the time taken for forests to grow, and the probably greater former water-flow.

The erosion of the Niagara Gorge began considerably later than that of Plum Creek, and probably dates from midway between the disappearance of the ice from Northern Ohio and from Quebec. If conditions have been uniform, the age of the Gorge would be 7000 years. As the Niagara
On Antigorite and the Val Antigorio, with Notes on other Serpentines containing that Mineral
Authors: Bonney T. G.
Published: October 2009

I.
The Original Specimen and the Val Antigorio
.

The exact locality of the type-specimen of antigorite is apparently unknown, as I found when preparing my portion of the paper by Miss Raisin and myself on the minerals forming serpentine. E. Schweizer, who first described it, states that the specimen (5 inches long, 2 inches wide, and 2 inches thick) was in the collection of D. F. Wiser of Zurich, who had bought it the year before

‘von einem mit Mineralien handelnden Bauer aus Oberwallis, nach dessen Aussage diese Substanz in kleineren und grösseren, bisweilen einen Fuss langen, dünnschiefrigen Platten im Antigoriothale bei Domo d'Ossola gefunden werden soil’;

and was unable to obtain any more precise information from the man. It has been subsequently noticed, among others, by Des Cloizeaux, Naumann, Hintze, Lévy & Lacroix, Tschermak, Brush, Rosenbusch, and Zirkel; the last adding to a full and precise description an extensive bibliography. But none of these authorities define the locality more exactly: each, as is not unnatural, being content with stating that the mineral came from the Val Antigorio, though Dr. Hussak and one or two of the later writers have noted its occurrence in other places. I failed, though some time was spent on the search, to obtain any better information from books on Italian geology, or the maps in our Society's Library; moreover, no serpentine is recorded in the Val Antigorio on sheet xviii of the Swiss Geological Survey-map. That, however, hardly amounted to proof of its non-occurrence, because
On the Application of Quantitative Methods to the Study of the Structure and History of Rocks
Authors: Sorby Henry Clifton
Published: October 2009

1. I
ntroduction
.

In the case of nearly all branches of science a great advance was made when accurate quantitative methods were used instead of merely qualitative. One great advantage of this is that it necessitates more accurate thought, points out what remains to be learned, and sometimes small residual quantities, which otherwise would escape attention, indicate important facts. Since it applies to nearly all branches of geology, it is necessarily a wide subject, but so connected together that it seems undesirable to divide it.

My object is to apply experimental physics to the study of rocks.

At least six different kinds of physical questions are involved, some of which have been sufficiently studied, but others require experiments which would be very difficult to carry out, and all that I can now do is to endeavour to deduce plausible results from what is known. In doing this, it may be necessary to assume cases sufficiently simple for calculation, which may but imperfectly correspond to natural conditions, so that the results may be only approximately correct. In some cases, facts seem to show that there are important properties connected with subsiding material which cannot be explained in a satisfactory manner. Notwithstanding this, it appears desirable to do the best that I can with the material at my disposal, hoping to lead others to do what I intended to do, and correct such errors as are now unavoidable.

In order to clear the way for subsequent detail, I describe a few general facts.