bluuebunny/crossref_metadata_2025 huggingface dataset:
XIV.—Maturity in the Female Mouse
Authors: Mirskaia L. , Crew F. A. E.
Published: June 2016

Puberty is defined as that stage of individual development characterised by the ability to elaborate functional gametes and by the physical ability to and the desire to play the appropriate rôle in mating. Maturity is defined as that stage of individual development characterised by the exhibition of the maximum fertility ratio and by the ability to produce viable offspring and to rear them.

It is shown that the age at attainment of puberty varies with different stock and with different conditions of husbandry, and that there can be no generally applicable standard. Each worker must standardise his own stock and his own environment.

There are considerable individual differences in the age at maturity, and these are referable to dissimilarities in genetic constitution and to differences in husbandry. In this experiment two groups of animals were involved, coloured and albino. The albinos reached puberty much earlier, showed a longer duration of the cornified stage before mating, a higher proportion of matings at first œstrus, a greater proportion of pregnancies following mating at first œstrus, and a slightly longer interval between first and second œstrus.
XV.—Do the Wireless Echoes of Long Delay come from Space outside the Moon's Orbit?
Authors: Störmer Carl
Published: June 2016

Mr President, Ladies, and Gentlemen,—I desire first of all to express my deep gratification at the great honour you have shown me by inviting me to give an address to this renowned Society. Scotland and Norway are closely united by bonds of friendship and also of kinship. There are many Norwegians with Scotch blood in their veins, just as there must be a large number of Scotch people who are descended from the Vikings who came here, long ago, and found the Scotch lassies so charming that they never returned to their own country!
XIX.—On Radiative Diffusion in the Atmosphere
Authors: Roberts O. F. T.
Published: June 2016

The processes of long-wave low-temperature radiation in the atmosphere have been studied with a view to investigating the extent to which they may be regarded as diffusion-like; the decrease of water-vapour with height is taken to be exponential, that of temperature to be constant up to the tropopause, and then to be zero. Full allowance is made for the radiation being diffuse, involving the functions; such properties of these functions as are required in the further work are studied. The expression for the upward flow of radiation is obtained in the form of a power series in the temperature gradient in the troposphere; the coefficient of the first power of the temperature gradient is defined as the “coefficient of radiative diffusion.” There is shown to be a certain amount of ambiguity about the coefficient so defined.

A model atmosphere resembling fairly well the conditions in N.W. Europe is considered: the upward flow of radiation and the coefficient of radiative diffusion are calculated; for this purpose we require Hettner's measurements of water-vapour absorption as modified by Simpson.

The effect of the heating of the ground during the day to a temperature above that of the air near by is then considered; it is shown that the study of the results of this factor which are of importance in the interpretation of continuous temperature records near the ground requires measurements of the absorption of water-vapour for the wave-lengths for which it is particularly opaque; these do not appear to exist.
XXI.—The Climate during the Pleistocene Period
Authors: Simpson G. C.
Published: June 2016

It is assumed that the glaciation of Northern Europe during the great Ice Age was due to a shift of the pole associated with appreciable variations of solar radiation.

The shift of the pole brought Europe into sufficiently high latitudes to permit of the formation of an ice-sheet; but the large variations of climate during the Ice Age, as shown by the interglacial epochs, were due to the oscillations of the solar energy.

If two complete cycles of solar radiation occurred during the Pleistocene Period, it is possible to account for four advances of the ice in the Alps as demonstrated by Penck and Brückner, but the interglacial epochs were not all warm. The Günz-Mindel and the Riss-Würm interglacial epochs occurred at the maximum of the solar radiation and were, therefore, warm interglacial epochs; but the Mindel-Riss interglacial epoch occurred at a minimum of solar radiation and was, therefore, a cold interglacial epoch.

At a maximum of solar radiation—that is, during a warm interglacial epoch—the climate of North-West Europe was warm and very wet, with a relatively small annual variation of temperature. As the intensity of solar radiation decreased, the mean temperature fell and the annual variation of temperature increased. At the same time the amount of precipitation decreased. The fall of temperature occurred sufficiently rapidly compared with the decrease in precipitation to cause the glaciers of the Alps to advance and for an ice-sheet to form over Scandinavia. As the solar radiation still further decreased, the lack of precipitation caused the glaciers of the Alps to retreat. At the minimum of solar radiation there was a cold interglacial epoch with low mean temperature, a large annual variation of temperature and very low precipitation; in fact, a truly continental climate.

With these changes of climate went a corresponding change in the flora, the sequence being: park land, forest, tundra, grass with sparse trees, and steppe. In this way it has been found possible to determine a sequence of climates and of fauna and flora for the whole Pleistocene Period, which is supported by the geological and archæological evidence available. In particular it is possible to arrange the sequence of human culture, the geological strata of East Anglia, and the history of the ice in the Alps into the scheme of climate change.

The two maxima of solar radiation were accompanied by increased precipitation in all parts of the world, so accounting for the two pluvial periods which are known to have occurred during the Pleistocene Period.
3. On some Phenomena of Indistinct Vision
Authors: Sang Edward
Published: June 2016

If an exceedingly small luminous object be placed in front of the eye, but out of the range of distinct vision, it appears to be a roundish bright disc traversed by various markings, and most of these markings are found to be permanent for the same eye, but different for the two eyes. The subject of the present paper is a modification of this appearance.

Instead of a luminous point let us take a very narrow luminous line, such as a small slit in the window-shutter, or the reflection of the light of a fire from a polished metallic rod, and let us put this out of focus by means of a pair of convex spectacles. On regarding the luminous line, without any attempt to adjust the eye to distinct vision, we perceive a long luminous band, the breadth of which varies with the distance of the line. When the luminous line is brought into focus, the apparent breadth becomes zero; it increases as the line is moved beyond or within the distance for distinct vision.
1. On the Colours of the Soap-Bubble
Authors: Brewster David
Published: June 2016

The colours of the soap-bubble have been the subject of frequent observation since the time of Boyle, Hook, and Newton, and they have been invariably ascribed “not to any colour in the medium itself in which they are formed, or on whose surfaces they appear, but solely to its greater or less thickness.” The author of this paper had been led to doubt the correctness of this opinion, and while repeating the beautiful experiments of Professor Plateau “On the equilibrium of liquid films,” he was led to discover the true cause of these colours, whether they are observed on the soap-bubble or on plane, convex, and concave films stretched across the mouths of closed or open vessels.
2. Note on the Action of Ammonia on Dicloracetone
Authors: Brown A. Crum
Published: June 2016

For some time I have been engaged in an attempt to replace the chlorine in monochloracetone and dichloracetone by other radicals, and with this object have acted upon them by means of cyanide of potassium, acetate of soda, and aqueous and alcoholic ammonia. In all of these cases the chlorine was removed as chloride of the alkaline metal or ammonium, and brown, tarry substances were produced, which resisted all attempts at purification. By the action of dry ammonia gas, however, I have obtained somewhat better results.
4. On a Method of ascertaining the Specific Gravity of Water which holds a minute quantity of Foreign Matter in Solution; or, on the Specific Gravity of Impure Water
Authors: Sang Edward
Published: June 2016

The determination of the degree of impurity of spring or well water is every day becoming of more and more importance. In order to discover how much foreign matter is contained in a sample of water, the chemist is under the necessity of drying up a quantity of it, and of weighing the residue. This operation is tedious, and gives a trust-worthy result only when the evaporation has been carried on in closed vessels from which atmospheric impurities have been carefully excluded; and, therefore, any assistance which can be obtained from mechanical measurements must be acceptable as affording a test for confirmation of the results.
3. Note on the Reality of the Roots of the Symbolical Cubic which expresses the Properties of a Self-conjugate Linear and Vector Function
Authors: Tait
Published: June 2016

Hamilton has shown that if

where α and β are given vectors, and A a given scalar, we have

where m, m1, m2, are scalars depending only on φ.

When the function φ is its own conjugate, i.e., when

ρ and σ being any vectors whatever, the vectors for which

form in general a real and definite rectangular system. This, of course, may in particular cases degrade into one definite vector, and any pair of others perpendicular to it; and cases may occur in which the equation is satisfied for every vector.
1. On the Arctic Shell Clay of Elie and Errol, viewed in connection with our other Glacial and more Recent Deposits
Authors: Brown Thomas
Published: June 2016

Referring to the papers formerly read before the Society in 1863 and 1864, the author first noticed the Section at Errol, its stratigraphical position and fossils, more especially the skeleton of a seal which had been found in the clay. He then described more in detail the different deposits as they occur in the neighbourhood of Elie. Since the shore Section was described in 1863 two new Sections had been examined, and the position of the different beds more fully ascertained. One was in the railway cutting extending from Elie Bridge to the Railway Station, in which, when first laid open, the series of deposits was remarkably well displayed.
1. On the Nature and Character of European Winter Storms, with the best means of giving Warning of their Approach
Authors: Russell R.
Published: June 2016

The object of this paper was to show the true character of storms, illustrated by those of 2d, 3d, and 4th December 1863. It was pointed out that the mode usually adopted of laying down the isobarometric lines was calculated to present an erroneous view of their figure or form. The laying down representative lines in round numbers of 5 millemetres in each, or in two-tenths of an inch of barometric readings, lead deceptively to the conclusion that the areas of least pressure were circular or elliptical.

It was then shown that the lines of equal pressures were ribbed into the latitudinal line of minimum barometer, which was usually found running north and south, sometimes nearly straight, but often curved, with its convex side towards the east. The minimum line of barometer was easily fixed by consulting the self-registering barometers. The minimum line of barometer was shown to have been on the meridian of London at 8 a.m. of the 3d December, and apparently nearly straight from Algiers to the Orkney Islands.
3. On the Radiant Spectrum
Authors: Brewster David
Published: June 2016

I have given the name of Radiant Spectrum to a phenomenon which I discovered in 1814, and which I described to this Society in the early part of that year.

It will be understood from fig. 1, which represents the brilliant radiation which surrounds a very small image of the sun, when it is formed either by reflection or refraction, or otherwise.
4. A Preliminary Notice of the Akazga Ordeal of West Africa, and of its Active Principle
Authors: Fraser Thomas R.
Published: June 2016

This ordeal poison is referred to in the works of Du Chaillu and Winwood Reade; and several of its toxic properties have been described by MM. Pecholier et Saintpierre. A few specimens were sent to this country in 1864 by the Rev. A. Bushnell of Baraka, and these were very kindly given to the author by Mr Thomson of Glasgow; and a further supply came from the same quarter in 1865. These gentlemen, and Dr Nassau of Bonita, supplied valuable and interesting information regarding its employment.

The poison is known in Africa as Akazga, Boundou (or M'Boundou), Ikaja, and Quai; Akazga being probably derived from nkazga, which signifies pain or hurt. It is used as an ordeal for the detection of real and superstitious crimes on the West Coast of Africa, in a large district which extends north and south of the equator, and many miles inland, and also in the adjacent island of Corisco.
8. Note on a celebrated Geometrical Problem
Authors: Tait
Published: June 2016

The following problem, originally proposed by Fermat to Torricelli, To find the point the sum of whose distances from three given points is the least possible, seems to have given considerable trouble to the older mathematicians, and even in modern times (see Gregory's Examples, p. 126) to have been solved in a very tedious manner. Simpler solutions have since been given (e.g., Cambridge and Dublin Mathematical Journal, viii. p. 92), but none, to my knowledge, so direct as that indicated by Quaternions. The object of this note is to show the simplicity of the quaternion method.
2. Note on the Hodograph
Authors: Tait
Published: June 2016

The object of the present Note is to show, by a few examples (of which, however, the last is the only one of any real importance), how easily the geometrical ideas supplied by Hamilton's beautiful invention of the Hodograph enable us to dispense with analytical processes in the establishment of some of the fundamental propositions connected with the motion of a single particle, besides many others which are merely curious; and also how they help us to understand the full bearing of some of the analytical methods. Some of the simplest of such geometrical investigations are given in “Tait and Steele's Dynamics of a Particle,” and will not be reproduced here; though a few of the results will be assumed,—as, for instance, that when the acceleration is directed to a fixed point, and varies inversely as the square of the distance from it, the hodograph is a circle, and the path a conic section, of which the point is a focus.
4. On the Changes produced by direct Chemical Addition on the Physiological Action of certain Poisons
Authors: Brown A. Crum , Fraser Thomas R.
Published: June 2016

In this paper the authors communicate the first results of an attempt to discover the relation which must exist between the chemical constitution and the physiological action of a substance. As the chemical constitution of the majority of physiologically active substances is unknown, they investigate the subject by examining the physiological action of a substance before and after the performance upon it of a definite chemical operation, introducing a known change into its constitution. The question is thus reduced to a problem in what may be called a chemico-physical calculus of finite variations.
2. On the Burning Mirrors of Archimedes, and on the Concentration of Light produced by Reflectors
Authors: Scott John
Published: June 2016

That the Roman ships were destroyed by burning glasses invented by Archimedes, is mentioned as a fact by most of the ancient writers, especially those who treat on mechanics, and their statements have been repeated by succeeding authors, without any doubts having been suggested until comparatively recent times. The earliest authorities on the subject are Diodorus Siculus, Lucian, Galen, Dion Cassius, and Pappus. It is much to be regretted that a work by the last named author on the Siege of Syracuse is now lost; but Zonares and Tzetzes, writers of the 12th century, in whose time it was extant, give quotations from it. That of the latter, translated pretty literally, runs thus:—“When Marcellus had placed the ships a bow shot off, the old man (Archimedes) constructed a sort of hexagonal mirror. He placed at proper distances from the mirror other smaller mirrors of the same kind, which were moved by means of their hinges and certain plates of metal. He placed it amid the rays of the sun at noon, both in summer and winter. The rays being reflected by this, a frightful fiery kindling was excited on the ships, and it reduced them to ashes, from the distance of a bow shot. Thus the old man baffled Marcellus, by means of his inventions.”
1. Observations relative to the desirableness of transporting from Alexandria to Britain the prostrate Obelisk presented to George IV. by Mahomed Ali Pacha
Authors: Alexander J. E.
Published: June 2016

In the month of September last (1867), when visiting the Great Exhibition in Paris, I was particularly struck with the fine appearance of the obelisk of Luxor in the Place de la Concorde, and I thought that as the French had taken the trouble and gone to the expense of moving this highly interesting monolith, it was a reflection on our nation and on the engineering skill of Britain that the prostrate obelisk at Alexandria (one of Cleopatra's needles, as it is commonly termed), was not occupying a place of honour in England or Scotland.

This obelisk was presented to George IV. many years ago by Mahomed Ali Pacha, who also generously offered to move it on rollers to the sea, from which it is 200 or 300 yards distant, and embarking it on rafts and lighters, convey it to a vessel for transport to England.
2. Note on a Recent High Tide on the East Coast of Britain
Authors: Robertson George
Published: June 2016

The greatest height to which the tide has ever been known to rise at any given place is of the utmost consequence to the marine engineer. It forms an important element in the design and in the estimate for any works in the sea; and any error on this point might lead to the most lamentable results both to life and property, especially in the construction of embankments for the reclamation of land.

I have therefore thought that a notice of the tide of the 8th of last month might not be uninteresting to the Society, as it is one of the highest, if not indeed the highest, that has ever been recorded with accuracy on the east coast of Britain, and the most remarkable example with which I am acquainted of the effect of wind in raising the level of high water on that coast.
2. On the History of the Sun's Distance Determinations; and on Scriptural and Scientific Probabilities
Authors: Petrie William
Published: June 2016

This paper was accompanied by two diagrams, one of them representing more particularly the features attending on space, and the probable errors of several modern determinations therein; and the other representing the chronological order of the events, or progress made by man from the earliest times, down to the present, in ascertaining that most important of all questions in astronomy and general physics, viz., the true mean distance of the earth from the sun.
2. On the Figures of Equilibrium of Liquid Films
Authors: Brewster David
Published: June 2016

This paper is a continuation of that read on 4th February 1867, and already published in the Transactions. Instead, however, of the liquid films being formed within systems of wires, hollow glass vessels are here employed. By using a single or double cone of glass open at both ends, and inserting within it small bubbles blown from a quill or tube with a small aperture, regular binary, ternary, or quaternary systems of films are produced. Thus, by first obtaining a plane film within the conical vessel, and then inserting upon it four small bubbles, a system is produced consisting of four hollow films, of curious curvature, united to one another respectively by vertical plane surfaces, and connected in their centres by a common plane film, which, by adopting certain precautions, may, with a little care, be made to assume either a horizontal or a vertical position.
1. Notice of Works designed by Sir Charles Hartley, C.E. for the Improvement of the Danube
Authors: Stevenson David
Published: June 2016

Having received from Sir Charles Hartley an interesting record of the works executed for the improvement of the Danube, to be presented to one of the Public Libraries in Edinburgh, I think its fittest destination is the Royal Society; and, on behalf of Sir Charles Hartley, I have to present the volumes on the table for the Society's acceptance.

It may not be uninteresting, in presenting these books, to describe, in a very few sentences, the work that has been executed for the improvement of the Danube, and the results that have been obtained.
4. On the Structure of the British Nemerteans; and new British Annelids
Authors: M'Intosh W. Carmichael
Published: June 2016

In the first part of this paper the anatomy and physiology of the Ommatopleans is described from the typical form O. alba, the variations and peculiarities presented by other genera and species being contrasted therewith. The descriptions are grouped under the following heads:—Dermal Tissues; Proboscidian Sheath; Proboscis; Digestive, Circulatory, and Nervous Systems; Cephalic Furrows, Pits, and Glands; Organs of Reproduction and Development.
Opening Address, Session 1868-69
Authors: Christison
Published: June 2016

Gentlemen,—It is now nearly five-and-forty years since I first opened my lips in this Society, a venturous young man, undertaking to instruct both practical men and men of science, as well as the public at large, all at the time keenly interested in the inquiry,—What were the principles for properly constructing burners for combustion of the light-giving gases? What the relative values of oil gas and coal-gas for giving out light, and which of the two should thenceforth be used for illuminating the world? At that time it was assuredly the farthest thing of all from my dreams that a period might come round when, by the voices of my Fellow-Members, I should be promoted to an office, the highest in learning or science, as the case may be, which Scotland can offer to their votaries,—held last by Sir David Brewster, and previously filled by the Duke of Argyll, Sir Thomas Brisbane, Sir Walter Scott, and Sir James Hall.
1. Notice of a Heart in which the Superior Vena Cava possessed a Valve at its Auricular Orifice
Authors: Turner
Published: June 2016

Whilst examining the heart in the body of one of the male subjects undergoing dissection in my practical rooms, in the early part of this session, the large size and fenestrated condition of the Eustachian valve attracted my attention. When the heart was removed from the body, and the auricle submitted to a more careful scrutiny, I observed that a valve was situated at the mouth of the superior vena cava.
2. On the Motion of a Pendulum affected by the Rotation of the Earth and other Disturbing Causes
Authors: Tait
Published: June 2016

1. Let α be the vector (from the earth's centre) of the point of suspension, λ its inclination to the plane of the equator, α the earth's radius drawn to that point; and let the unit vectors i, j, k be fixed in space, so that i is parallel to the earth's axis of rotation; then, if ω be the angular velocity of that rotation
2. Note on the Determination of Heights, chiefly in the Interior of Continents, from Observations of Atmospheric Pressure
Authors: Buchan Alexander
Published: June 2016

The weight or pressure of the atmosphere is ascertained by the mercurial barometer, the aneroid, or from the temperature of the boiling point of water. The height of a hill is measured barometrically, from observations made simultaneously at its base and top, and the application of certain well-known formulæ. The height of a place at no great distance from another place whose height is known, and at which observations are made about the same time, may similarly be ascertained with a close approximation to the truth.

But, with regard to places far from any place of known elevation, or from any place at which meteorological observations are made, it is plain that the height can only be computed by assuming a certain pressure as the sea-level pressure at that place.
1. Motion of a Palladium Plate during the formation of Graham's Hydrogenium
Authors: Dewar James
Published: June 2016

Graham, in continuing his exhaustive researches on diffusion, has recently examined the relation of gases to various colloid septa. The remarkable discovery of Deville and Troost of the permeability of platinum and iron by hydrogen at a red heat, he lias expanded into a general examination of the relative rates of passage, at high temperature, of the various gases through different metallic septa. Further, he has proved that different metals have a specific occluding power over certain gaseous elements, retaining them in combination at low temperatures, although the absorption took place at a red heat. Of the many astonishing discoveries made during the course of these investigations, probably the most remarkable is the occlusion of hydrogen by palladium. This metal, whether in the form of sponge or hammered foil, when heated and cooled in an atmosphere of hydrogen, absorbed between six and seven hundred times its volume—increasing to the enormous occlusion of 982 volumes, when the metal used had been deposited by voltaic action.
Some Observations on Free, An-atomic, or Transmissible Power
Authors: Wyld R. S.
Published: June 2016

This is an abstract of the first of two papers on the subject, prepared for the Society.

Physical bodies may be held, in accordance with chemical science, to consist of aggregations, either of material atoms, or of atomic circles, or centres of force.

There are certain exhibitions of physical power observed in connection with those atomic bodies, the laws and actions of which are in the highest degree worthy of study. Mr Wyld calls power exhibited in this way, free an-atomic or tranmissible power.
On a New Synthesis of Ammonia
Authors: Catton A. R. , Main P. T.
Published: June 2016

It having been shown by one of us that formic acid is produced by the union of carbonic acid and nascent hydrogen, it occurred to the authors to try whether other gases might not be made to unite directly with nascent hydrogen. Such experiments gave the prospect of being of especial interest in the case of nitrogen, as it was possible the synthesis of ammonia might thus be effected by the direct union of nitrogen and hydrogen.
The Mean Pressure of the Atmosphere, and the Prevailing Winds for the Months and for the Year. Part II
Authors: Buchan Alexander
Published: June 2016

In Part I., read 16th March 1868, in which was discussed the Mean Pressure of the Atmosphere over the Globe for July, January, and the year, the method by which the Isobaric Charts were constructed was detailed at length. Since March 1868, valuable additional information has been obtained from Australia, New Zealand, Tasmania, Africa, South America, the west coast of North America, Iceland, and from a few isolated stations in Europe and Asia. The period for the British Islands has been extended so as to include the eleven years from 1857 to 1867.
On the Boulder-Clay of Europe
Authors: Milne-Home D.
Published: June 2016

It was explained that this deposit, known in Scotland as Till or Boulder-Clay, prevails also in Ireland, the Isle of Man, England (north of the Thames), Denmark, and Sweden, though much less abundantly in these last countries. It exists also in the Hudson's Bay districts, and at the south extremity of South America.

It had been a subject of perplexity to geologists ever since attention was drawn to it, fifty years ago, by Sir James Hall of Dunglass, whose papers are in the Transactions of this Society.

About the year 1840 a theory was started to account for the boulder-clay, and other phenomena allowed to be connected with it, by the action of glaciers.
Hegel and the Metaphysics of the Fluxional Calculus
Authors: Smith W. R.
Published: June 2016

The object of this paper is to consider the mathematical value of Hegel's discussion of the fluxional calculus. This discussion, as contained in several notes in the “Logik,” professes to evolve the true principle of the calculus in a form free from the inconsistencies of the usual processes, and to show how this principle may be rendered useful in the solution of problems. To clear the way for this new theory, Hegel engages in a sharp polemic against the expositions of several parts of the calculus given by Newton and others.
Preliminary Note on the Antagonism between the Actions of Physostigrna (Calabar Bean) and Belladonna
Authors: Fraser Thomas R.
Published: June 2016

In this paper the author described a number of observations which appear to demonstrate that the fatal action of certain doses of physostigma may be prevented by the administration of atropia.

The following plan was adopted for the investigation:—After the minimum fatal dose of each poison bad been approximately determined for rabbits and dogs of different weights, a fatal dose of one of the poisons was administered along with a certain dose of the other, and, if death did not result, the same animal was subsequently killed by a dose of one of the poisons equal to or less than that given in the combination.
3. Algebra of Relationship.—Part II
Authors: Macfarlane A.
Published: June 2016

At the end of my previous paper on the Algebra of Relationship (Proc. Roy. Soc. Edinb., vol. x. p. 224), I promised to return to the investigation of the subject, as it seemed capable of further extension. This anticipation has proved correct, and I have now the honour of bringing before the Society the further developments I have made.

In this investigation we consider a particular class of objects, and that class is in its widest extent mankind, by which term I mean the entire number of men who have existed, exist, or will exist. The universal properties of the symbols are deduced from the universal properties of mankind. In our consideration of this universe of mankind, we restrict our attention to the classes into which it is divided by qualities depending on ties of anterior or of posterior relationship, that is, of consanguinity or of affinity.
1. On Dust, Fogs, and Clouds
Authors: Aitken John
Published: June 2016

Dust, fogs, and clouds seem to have but little connection with each other, and we might think they could be better treated of under two separate and distinct heads. Yet I think we shall presently see that they are more closely related than might at first sight appear, and that dust is the germ of which fogs and clouds are the developed phenomena.

This was illustrated by an experiment in which steam was mixed with air in two large glass receivers; the one receiver was filled with common air, the other with air which had been carefully passed through a cotton-wool filter and all dust removed from it. In the unfiltered air the steam gave the usual and well-known cloudy form of condensation, while in the filtered air no cloudiness whatever appeared. The air remained supersaturated and perfectly transparent.
2. Solar Eclipse, 31st December 1880
Authors: Sang E.
Published: June 2016

The elements for the compution of eclipses are given in the “Nautical Almanac” with precision sufficient for all ordinary purposes; but, when we wish to compare the lunar ephemeris with actual observation for the purpose of verifying or of improving our data, we must go somewhat more minutely into the investigation.

Thus, in the List of Elements, p. 403, the changes in the right-ascension and declination of the sun and moon are supposed to be proportional to the times, while the moon's geocentric semidiameter, as well as the horizontal parallax, is supposed to be constant during the eclipse. In this way some exceedingly small errors are introduced into the calculation.
2. Meconic Acid
Authors: Dott D. B.
Published: June 2016

Although meconic acid is constantly taken, even in the most recent handbooks of chemistry, as an instance of a tribasic acid, it is by no means certain that it possesses that nature. Some years ago, Dittmar and Dewar investigated the matter, and came to the conclusion that meconic acid is dibasic though triatomic; but their experiments are not supposed to completely elucidate the subject. All published statements regarding this acid are consistent with it being only dibasic, if we except one or two analyses of its metallic salts. Only two ethyl ethers are known, while hydromeconic acid, which is formed from meconic acid by the action of sodium-amalgam, forms dibasic salts alone. With morphia and with aniline tribasic compounds are not known, though the dibasic salts are easily prepared.
7. Note on the Temperature Changes due to Compression
Authors: Tait
Published: June 2016

The author described the results of a number of experiments, made during the examination of the “Challenger” Deep-Sea Thermometers, with the view of testing, at pressures of 3 tons weight per square inch and upwards, Thomson's formula for the heat developed by compression (Proc. Roy. Soc., 1857, p. 568).

When, for instance, the bulb of one of the thermometers was surrounded by a shell of lard upwards of half an inch thick, the total effect produced by a pressure of 3½ tons weight was 5° F.; while for the same pressure, without the lard, the effect was only l°·8 F. The temperature of the water in the compression apparatus was 43° F., so that the temperature effect due to the compression of water was less than 0°·2 F. In obtaining this number it was assumed from Kopp's experiments that the coefficient of expansion of water at a temperature t° C., near its maximum density point (roughly, 4° C.), . Hence the effect due to the compression of the lard was 3°·4 F., or about 1° F. per ton weight. This is subject to corrections (which will increase its value) depending on the heat developed by friction in the pump and in the narrow connecting tubes, and on another cause not yet fully ascertained.
2. On the Histology of the Pedicellariæ and the Muscles in Echinus sphœra, Forbes
Authors: Geddes Patrick , Beddard Frank E.
Published: June 2016

This paper contains a detailed account of the structure of the soft parts of the four varieties of Pedicellariæ in this species describes particularly certain new pseudo-skeletal structures, and concludes with a reconciliation of the hitherto contradictory views as to the structure of Echinoderm muscles.
4. On some Effects of Rotation in Liquid Jets
Authors: Tait
Published: June 2016

The author had noticed that a jet of mercury from a funnel, falling horizontally and nearly tangentially on a slightly inclined glass plate, seemed to roll upwards along the plate. Attributing this to a rotation of the jet, he endeavoured, with success, to re-produce the phenomenon with water jets escaping from a rapidly rotating tube, and falling on a slightly inclined glass surface covered with a thin layer of paraffin.
2. Stilbite, from Kerguelen's Island
Authors: Liversidge A.
Published: June 2016

I am indebted to the kindness of my friend Mr J. Y. Buchanan, M.A., the chemist and physicist to the “Challenger” expedition for the specimen which forms the subject of this note.

In speaking of the geology of Kerguelen Island, Mr Buchanan thus describes the occurrence of this zeolite (vide Proc. Roy. Soc., vol. xxiv. p. 617).

“The horizontal beds which form the mass of the land are basaltic, and vary from 10 to 20 feet in thickness, being generally compact; but, in ascending the hill, beds are met with frequently, which contain large amygdaloidal cavities filled with zeolites, principally analcite and heulandite (stilbite). These minerals are very plentiful in this part of the island, and when rounded by the action of the water they form remarkable white pebbles on the otherwise darkcoloured volcanic sand. Up to the summit the alternation of beds of compact sub-columnar rock of amygdaloid is pretty regular.
3. On a Simple Form of Selenium Cell, and Experiments therewith
Authors: Blyth James
Published: June 2016

The cell is constructed as follows:—

Take a brass crop-comb of the kind usually worn by little girls. Cut off from it two equal parts, each about 4 inches long. From each part cut out each alternate tooth, and bend round each part in the form of a cylinder, soldering the ends together with hard solder. Take a glass tube about 4 inches long and having a diameter equal to the diameter of the cylinder. Place the brass cylinders upon the glass tube, with the teeth facing each other, and adjust them so that each tooth left takes the place of one which has been cut out, taking care that the teeth do not touch each other nor the solid parts of the cylinder.
4. Dust, Fogs, and Clouds
Authors: Aitken John
Published: June 2016

Since I made my first communication to this Society on Dust, Fogs, and Clouds, most of the experiments have been repeated under different conditions.

Taking advantage of the late extremely cold weather, the apparatus was placed in the open air, and experiments made with it, the temperature of the air at the time being 8° Fahr. The result was the same as at higher temperatures. Cloudy condensation with dusty air; no condensation with filtered air.

The experiment in which dustless gas was burned in dustless air was repeated. The glass jet which was used for burning the gas in the first experiment, being now replaced by a platinum one, as it was thought possible the dust produced when the glass jet was used might be the result of the decomposition of the glass by the heat. Before makiug the experiment, the platinum jet was highly heated, to cleanse and make it inactive. The result, however, was as before. Dense fogging whenever the gas was lit, and the fogging continued so long as the gas was kept burning.
5. Note on Thermal Conductivity, and on the Effects of Temperature-Changes of Specific Heat and Conductivity on the Propagation of Plane Heat Waves
Authors: Tait
Published: June 2016

In the great majority, at least, of investigations (experimental or mathematical) connected with conduction of heat, it has been assumed that the known changes of specific heat of metals do not require to be taken into account. Thus Ångström says, even in his paper on the Change of Conductivity with temperature (Pogg. 118, 1863):—“Da indess diese Veränderungen, soweit man sie kennt wenigstens innerhalb der bei den Beobachtungen vorkommenden Temperaturgränzen, nicht bedeutend sind, …,… so müssen dieselben den Werth des Wärmecoefficienten nur unbedeutend afficiren können.”
5. Note on a Singular Problem in Kinetics
Authors: Tait
Published: June 2016

The following problem presented itself to me nearly thirty years ago. I cannot find any notice of it in books, though it must have occurred to every one who has studied the oscillations of a balance:—

Two equal masses are attached to the ends of a cord passing over a smooth pulley (as in Attwood's machine). One of them is slightly disturbed, in a vertical plane, from its position of equilibrium. Find the nature of the subsequent motion of the system.

The interest of this case of small motions is twofold. From the peculiar form of the equations of motion, it is of exceptional mathematical difficulty. This is probably the reason for its not having been given as an example in Kinetics. And from the physical point of view it presents a very beautiful example of excessively slow, but continued, transformation of mixed potential and kinetic energy into kinetic energy alone.
2. The Action of Heat on Thioformanilid
Authors: Nicol W. W. J.
Published: June 2016

While at work during the past session in the Berlin Laboratory, it was suggested to me by Professor Hofmann, that I should examine the behaviour of thioformanilid when submitted to various degrees of heat. The thioformanilid employed was prepared by heating formanilid with penta-sulphide of phosphorus, the resulting mass was treated with dilute caustic soda, and the alkaline solution of thioformanilid thus obtained was mixed with excess of hydrochloric acid, when impure thioformanilid separated out; this was purified by crystallisation from hot dilute alcohoL The crystals thus prepared melted at 137°–138° C., the melting-point of pure thioformanilid being 137.5° C. (Hofmann).
1. On Galvanic Polarisation
Authors: Helmholtz
Published: June 2016

In 1872 I wrote a paper on galvanic currents, which continue for a long time in an electrolytic cell, under the influence of an electro-motive force, too feeble to effect electrolytic decomposition. I tried at that time to prove that the long duration of these currents was caused by oxygen dissolved in the water of the electrolyte, combining with the hydrogen, which is carried by the electrolytic motion to the cathode. So the oxygen, which existed formerly near the surface of the cathode, is taken away, and instead of it the same amount of oxygen is liberated at the anode. This can return by diffusion to the cathode, and so the same action can go on without end. It appears as a current producing no electrolytic action. I called it “Electrolytic convection.”
3. On the Crushing of Glass by Pressure
Authors: Tait
Published: June 2016

In the course of my examination of the “Challenger” thermometers, I was once surprised by a sudden bell-like vibration of the massive iron cylinder (nine inches thick) in which the apparatus to be tested was enclosed. This was due to the giving way of the protecting-sheath of one of the thermometers, at a pressure of a little over four tons weight on the square inch. When the pressure was let off, the bulb of the thermometer was found to have been crashed to an almost impalpable powder. I then determined to make a set of experiments with the view of finding under what amount of distortion glass gives way. For this purpose I employed the smaller compression apparatus which I have already described to the Society. Its capacity is about ten cubic inches only, so that a couple of strokes of the pump produce a pressure of three to four tons weight.
3. Note on Chemical Affinity and Atomicity
Authors: Durham William
Published: June 2016

The theory of “Valency” or “Atomicity,” while explaining satisfactorily many chemical phenomena, still leaves unexplained many facts, such, for instance, as the varying atomicities of several elements, the composition of double salts, water of crystallisation, &c. This arises from assuming that chemical affinity acts in an atomic indivisible manner, which is not warranted by the facts. If we take, for instance, nitrogen in the compound, NH3 and NH4Cl, it acts in the one case as a triad, while in the other it is said to be a pentad. Now, ïn the case of the NH4Cl in this view, we have the chlorine represented as directing all its affinity to the nitrogen, for which it usually has such a feeble affinity, while it has no action on the hydrogen, for which its affinity is usually so intense. Now, if we get rid of the idea of the atomic action of affinity, we may represent the chlorine dividing its action among all the four atoms of hydrogen, giving on the average ¼ to each; and the nitrogen, in the same manner, giving ¾ to each; and thus, the whole molecule is bound together.
2. Preliminary Report on the Tunicata of the “Challenger” Expedition. Part IV
Authors: Herdman W. A.
Published: June 2016

The family Molgulidœ was established by Lacaze-Duthiers in 1877, and distinguished from the Cynthiadœ, with which it had formerly been united by Heller.

Lacaze-Duthiers divides the species known to him into four genera,—Anurella, Molgula, Ctenicella, and Eugyra,—of which Anurella forms a sub-family or section the Molgulidœ anurœ, the other three constituting the Molgulidœ urodelœ. The character by which Anurella is distinguished from the other genera is the tail-less amoeboid larva; but this most interesting developmental difference does not seem to be accompanied by any structural features in the adult animal, and consequently it becomes impossible to distinguish the genus unless one examines the animal alive and at the breeding season.
On the Classification of Statistics and its Results
Authors: Geddes Patrick
Published: June 2016

§ 1. Every one may readily notice that the collection of statistical information goes on around us to a vast and constantly increasing extent; not simply in the periodic census, but in the daily labours of the Registrar-General's Department, of the Board of Trade, and the like. Such functions are carried on in every civilised country by many special statistical bureaux; a statistical society exists in almost every great intellectual centre, and an International Statistical Congress, which has proposed to itself the vast object of accumulating, co-ordinating, and comparing the whole body of national statistics, has met periodically since 1853.
2. On the State of Carbon in Iron and Steel: a New Hypothesis of the Hardening of Steel
Authors: Marsden R. Sydney
Published: June 2016

This paper first treats of the composition and properties of the different kinds of iron, known as wrought iron, steel, and cast iron, and especially of the changes which steel undergoes on being heated to redness and then suddenly cooled by plunging it into water, mercury, or oil, and known as hardening; also of the peculiar property known as tempering, by which the hardness and brittleness can be removed.
5. Optical Notes
Authors: Tait
Published: June 2016

The second figure in Professor Everett's note (ante, p. 360) has reminded me of my explanation of a phenomenon which I have repeatedly seen for more than twenty years in the College. When sunlight enters my apparatus-room through a vertical chink between the edge of the blind and the window-frame, the line of light formed on the wall or floor shows a well-marked kink. Similar phenomena, though not usually so well marked, are often seen in old houses, when the sun shines through the chinks of a Venetian blind. They are obviously due to inequalities (bull's-eyes) in the glass which was used more than a generation ago for window-panes. Professor Everett's figure, which was drawn for a cylindrical lens, represents the general form of a central section of such a bull's-eye.
2. On a Specimen of Sowerby's Whale (Mesoplodon bidens) captured in Shetland
Authors: Turner
Published: June 2016

Sowerby's whale is one of the rarest of the cetacea which frequent the British seas. It was first recognised as a distinct species by Mr. James Sowerby, from a specimen cast ashore in 1800 on the coast of Elgin, and named by him Physeter bidens. From that time to the present no properly authenticated specimen has been obtained in Scotland, although it is not unlikely that a skull in the Museum of Science and Art in this city, a description of which I gave to this Society in 1872, may have belonged to an animal captured in the Scottish seas. Two, if not three, specimens have been obtained on the Irish coast, but I know of no example of this whale having been caught in England. In my former communication to this Society, I referred to two specimens taken in France (Havre, Calvados), one at Ostend, one on the coast of Norway, and one on the coast of Sweden, and this completed the record of this animal so far as I could find a reference in zoological literature.