The President, on opening the Session, stated that—

At the statutory meeting, held on 23rd November 1896, the President was appointed (with power to name a substitute) to represent the Society at the British Association Commission on a National Physical Laboratory.

At a meeting of Council on 7th May last, the President and Dr Murray were appointed members of the Consultation Committee in connection with the proposed Catalogue of Scientific Literature.

At a meeting on 21st May 1897, Dr Murray, Dr Traquair, and Mr Cadell of Grange were appointed to represent the Society at the International Russian Congress at St Petersburg, and Principal Talmage was subsequently added to the above-mentioned representatives.

Professor D'Arcy Thompson, a member of our Council, was reappointed a Commissioner to report on the aspects of the Seal Fishery in Behring's Straits, and on its international relations.

The four instruments, the traces of which are examined, are the declination, horizontal force, and vertical force magnetographs, and the barograph. The instruments being not seismological, the following discussion of the character of the disturbance, based upon the traces of these instruments, must obviously be regarded as an attempt at explanation, and as an attempt only. Colaba, it appears, was situated well outside the area of perceptible shaking, and the distance of the Observatory from the centre of disturbance, whether suboceanic or otherwise, was sufficiently large to render the disturbance as it reached Colaba very feeble, and yet it was just sufficiently strong to leave some record of its peculiar characteristics. All traces have been enlarged about two and a half times, but the exact time and measurements have been derived from the original traces.

The theory of mass action leads to very simple consequences when applied to the determination of the velocity of chemical processes which take place in homogeneous solution. If the reaction is pure and irreversible, the initial concentrations of the reacting substances have only to be known in order to obtain an expression which shall give for every value of the time (measured from the beginning of the reaction) the corresponding extent to which the action has taken place, one constant being involved. This constant, which is characteristic of the reaction, is called its velocity constant, and for a given medium and a given temperature is invariable. Reactions have been classified by Van't Hoff into unimolecular, bimolecular, trimolecular, etc., reactions, according to the number of molecules which interact; and to every class there corresponds an equation by means of which the velocity constant is determined, the expressions for the constants differing from each other in form from class to class. For example, if the initial concentration of each of the reacting substances be A, the time t, and z the extent to which the action has progressed at the end of the time t, then the following expressions will be constant:—

In a paper, communicated to the Society in February 1897, the author drew attention to increase in electrical conductivity as a characteristic of photo-chemical action.

This increase in electric conductivity may be explained by assuming that light acts either in the direction of increased conductivity, or as a disturbing agent on molecular systems having an inherent tendency towards rearrangements involving increased conductivity.

It may be that both assumptions are correct.

Since making this communication the author has been engaged in experimental investigation, undertaken in order to elucidate this subject further—more particularly in its chemical aspect.

The behaviour of nitric acid with respect to light appeared especially suggestive. Nitric acid on progressive dilution with water becomes less and less subject to decomposition by light, until, as that dilution which corresponds to maximum conductivity is approached, the action of light seems to cease altogether, so that nitric acid at all dilutions greater than that corresponding to its maximum electrolytic conductivity appears to be unaltered by light. It seemed, therefore, desirable to investigate experimentally the purely chemical behaviour of nitric, hydrochloric, and sulphuric acids at different degrees of dilution with water. The investigation is now sufficiently far advanced to justify the communication to the Society, in this preliminary note, of some of the conclusions which have been arrived at.

§ 1. In § 10 of our paper “On Electrical Properties of Fumes proceeding from Flames and Burning Charcoal,” communicated to this Society on 5th April, results of observations on the leakage between two parallel metal plates with an initial difference of electric potential of 6·2 volts between them, when the fumes from flames and burnings were allowed to pass between them and round them, were given. The first part (§§ 1–4) of the present short paper gives results of observations on the leakage between two copper plates 1 centimetre apart, when one of them is kept at a constant high positive or negative potential; and the other, after being metallically connected with the electrometer-sheath, is disconnected, and left to receive electricity through fumes between the two.

The method of observation (see fig. 1) was as follows:—Two copper plates were fixed in a block of paraffin at the top of a round tinned iron funnel 96 centimetres long and 15·6 centimetres internal diameter. A spirit-lamp or a Bunsen burner, the only two flames used in these experiments, was placed at the bottom of the funnel, 86 centimetres below the two copper plates. One terminal of a voltaic battery was connected to one plate, B, and the other terminal was connected to the sheath of a Kelvin quadrant electrometer. The other copper plate was connected to one of the pair of quadrants of the electrometer in such a way that by pulling a silk cord with a hinged platinum wire at its end, this copper plate and this pair of quadrants could be insulated from the sheath of the electrometer and the rest of the apparatus.

The fact that the salmon comes from the sea and spawns in the river has induced the supposition that this fish ascends the river only for the purpose of spawning. That the supposition is not always justifiable seems, however, sufficiently shown by the fact that clean-run salmon with undeveloped reproductive organs may be found in fresh water during the spawning season, and indeed at any season of the year, and also by the fact that a spring run of fish is usual. “When we regard the head waters of many of our rivers as localities for the natural propagation of the salmon, we find, however, that, except at the spawning season, adult fish are never present. When, at the same time, we remark that the fish which ascend to those waters during the winter months are all sexually ripe, we may fairly conclude that the fish are impelled to migrate to those head waters for the express purpose of spawning.

It has been said that the shads (Clupea allosa, and C. finta) and the sea lamprey (Petromyzon marinus) are examples of fishes which have a spawning habit analogous to that of the salmon, since they also ascend rivers for the purpose of propagating their species. Their habit is, however, more analogous to that of the comparatively few salmon which penetrate at once to head streams and tributaries, than to the fishes which inhabit the lower reaches of a salmon river. They ascend for a limited period only, and seek again the salt water whenever the operation of spawning is completed. They are marine fishes which spawn in fresh water. The common eel may be taken as an example of a fresh water fish which spawns in sea water.

Hydroxylamine, NH2OH (oxyammonia), is an unstable substance only to be had in weak solutions. It forms many salts, two of which, the sulphate, 2(NH2OH.)H2SO4, and the hydrochloride, NH2OH.HCl, are to be found in commerce.

My attention was first directed to this substance, hydroxylamine, by seeing a reference to the work of Loew and Bokorny on the chemical constitution of protoplasm, and to their theory that there is present in it a group of atoms of the nature of an aldehyde. To this group of atoms they attribute the energy of living protoplasm, and state, in support of this, that hydroxylamine, which is said to have a strong affinity for aldehyde, rapidly kills protoplasm in algæ and the young shoots of plants.

My intention was to use both hydroxylamine and its salts upon some forms of animal protoplasm, but so far the hydrochlorate is, the only preparation that has been available. This salt is easily soluble in water and is extremely acid. It is difficult to neutralise it exactly, as at a certain point it reacts to both red and blue litmus simultaneously. Solutions of 1 per cent, strength were employed almost entirely.

Dr Donald, who sailed on board the “Active” in the voyage of 1892–3, has given a short account of the discovery of a number of fossils by Captain Larsen on Seymour Island, to the north of Snow Hill, in January 1893 (Geographical Journal, vol. ii. p. 438, 1893). Some of these fossils were sent to Professor James Geikie, and at his request we gave an account of them to the Royal Society of Edinburgh, June 4, 1894 (Trans. Roy. Soc. Edin., vol. xxxvii. p. 707; see also Dr Murray, Geog. Journ., vol. iii. p. 11, note, 1894). The fossils do not appear to have been found in situ. Captain Larsen reports of the locality “that he found no traces of vegetation there, the surface being formed of volcanic débris and numbers of these fossils” (Dr Donald's notice, p. 438, loc. cit.).

The condition of the fossils, however, would seem to indicate that the mother rock from which they were derived could not be at any great distance from the spot where they were picked up.

As the few species of Mollusca represented by these fossils seemed to us to find their nearest allies among Lower Tertiary forms, and to be near to certain species known from Patagonia (Darwin, Geol. Obs. Sth. Am., 1846), we were led to conclude that these new discoveries indicated the occurrence of Lower Tertiary rocks in Seymour Island.

In a “Mémoire sur la déduction, d'un seul principe, de tous les systèmes crystallographiques avec leurs subdivisions,” by Axel Gadolin, there is given a proof that, if we assume the law of rational indices, only digonal, trigonal, tetragonal, and hexagonal axes are possible with crystals. This proof is adopted by Groth in the last edition of his Physikalische Krystallographie, 1895. The proof which I shall now give, although somewhat similar in general principle, is decidedly simpler than that of Gadolin. It is assumed in the former that an axis of symmetry is necessarily a possible edge or zone axis, and that there are possible edges perpendicular to any axis of symmetry, i.e., that the plane to which it is normal is a possible face. These general propositions are not, so far as I am aware, to be found in text-books, although tacitly assumed in certain cases, and a proof of them, as also of two similar ones concerning planes of symmetry, is therefore indicated here before treating the main problem.

Towards the end of the year 1893, I received from Captain Thomas Robertson of Dundee, master of the steamship “Active,” a number of specimens of rocks which he had collected in the Antarctic regions during a sealing expedition. In letters to me he gave the following particulars regarding these specimens:—“They were all taken from one place in Dundee Island. We had not time to land and take specimens from other parts. Dundee Island, so named by me, is a separate piece of land, close to Joinville Island, and all the stones I sent you were picked up on a beach at its south-west end. I had a boat sealing on Joinville Island, but they brought no specimens of rock on board. The round flat piece of light-coloured granite I broke off a piece the size of a man's head, the day I sent off the box to you. The small piece of blue basaltic rock I broke off at the same time, not to make the box too heavy. You have all the others as they were found. The southwest end of Dundee Island is a long low point which I named ‘Welchness.’ There are high cliffs up from the ness, from which the pieces of granite could have come, or they might have been carried by the ice.

The quality of the human voice depends on the same laws as those determining the quality, klang-tint, or timbre of the tones produced by any musical instrument. Tones of a mixed character, that is to say, composed of a fundamental and partials, are produced by the vibrations of the true vocal cords, and certain of those partials are strengthened by the resonance of the air in the air-passages, and in the pharyngeal and oral cavities.

So strongly may certain of these partials be reinforced, as to obscure or hide the fundamental tone, and give a peculiar character to the sound. These, however, are only general statements, and there are still many difficulties in the way of a true interpretation of voice-tones. In the first place, we observe that we may sing a scale, using one sound for each note, such as la, la, la, etc. Or, by putting the mouth in a certain position, we can pronounce the so-called vowels, a, e, i, o, u (ou as the u in prune), uttering the sounds ah, ā, ē, o, ou. As we do so, we notice that each sound appears to the ear to have a pitch of its own, different from that of the others.

For about seven years I have been, engaged upon the investigation of the impressions made by vowel sounds on phonograph cylinders.

The close accordance of my results with those of Prof. L. Hermann of Königsberg and Dr Hugo Pipping of Helsingfors, though obtained by widely different methods, showed, 1st, that the method by which I obtained my results, although much simpler and easier to manage than those of the above-mentioned investigators, yields, nevertheless, very satisfactory results; and 2nd, that the same vowel sounds are formed almost exactly in the same manner by persons of different age, sex, and nationality.

In the only scientific paper which, till now, I have published on this subject, in 1891, only the vowel a (as in hard) was treated in a somewhat elaborate manner, but since then I have applied my method to other vowels as well.

As I have altered my method of research a little in the course of time, it may be useful to give a somewhat detailed description of my present mode of procedure.

It is a great advantage and satisfaction to work from curves taken by the phonograph itself, because it is then possible to reproduce and verify by actual hearing the sound supposed to be represented by given curves. This ought always to be done, even with the phonograph, and the slightest change of timbre should be carefully noted; for the given curve represents not really the original sound, but the sound given back by the phonograph. Every plate or membrane vibrates more readily and strongly to some pitches than to others, and in a composite sound it is almost inevitable that some of its elements are recorded with more, and others with less, than their original relative force. Different vibrators hence yield quite different-looking phonograms for the same sound. In vowels it seems fortunately to happen that considerable changes in the relative force of the component vibrations may occur without altering the vowel. It is the pitch of the components which matters; and that is not altered by an efficient vibrator. Assuming a knowledge of the methods by which the record dug vertically into the phonographic cylinder is displayed horizontally for examination and analysis, we note that a satisfactory Fourierian analysis demands a sufficient number of measurements.

§ 1. Let X and Y be two metals, of which X is electrically positive to Y in the Volta-contact series for dry metals, and make an incomplete circuit of them as indicated in the diagram, with X and Y metallically connected at an interface J, and free surfaces II, KCC exposed, with ether or air, or any gas or insulating fluid, between them. Let CC be a movable slab of the Y-metal, resting frictionlessly on a fixed surface KK of the game metal. If left to itself the movable slab would, in virtue of electric attraction, as we shall see, oscillate on the two sides of the middle position in which the whole of its upper surface is opposite to II. We shall suppose it held by applied force F in any position, or moved, or allowed to move, from any one position to any other, at our pleasure.

§ 2. Suppose now our apparatus to be given with no excess of either electricity above the other, and to be insulated in air or ether at a distance from all other bodies great in comparison with its own dimensions, and with no electrified body near enough to it to produce sensible electrification through influence. Every part of the X-surface will be found positively and every part of the Y-surface negatively electrified, provided each surface is of perfectly uniform Volta-quality throughout its extent; but the electric surface-densities of the opposite electrifications will be everywhere exceedingly small, except in and near the portions of II and CC closely opposed to one another.

§ 1. In a verbal communication to the Royal Society of Edinburgh in 1876, under the title “Thermodynamic Motivity,” I suggested the name motivity to express energy, whether thermal or of any other kind, available to generate velocity in molar matter, or to move molar matter against resisting force. By molar matter I mean matter as we know it, consisting, as we believe, of vast numbers of atoms or molecules. Only the title of this communi- cation was published in the Proceedings of tlie Royal Society. a short report of it was published in the Philosophical Magazine for May 1879, in which it was pointed out that a “very short and simple analytical method of setting forth the whole non-molecular theory of thermodynamics” might be founded on the consideration of Motivity and Energy as two functions of all the independent variables specifying a body, or a system of bodies, or some definite apparatus under consideration:—apparatus, as I shall call it for brevity, to include every case, even such as a single crystal. The object of the present communication is to carry out this proposal.

§ 2. Let the apparatus be given all at one temperature t. Denote by g1, g2, g3, etc, the other variables by which its condition is specified. These will in many cases be geometrical, specifying elements or co-ordinates, such as strain-components, expressing change of bulk or shape of a piece of crystal or other elastic solid under stress; or positions of pistons in a pneumatic apparatus; or area, or curvature, of a free liquid surface in an application to theory of capillary attraction; or positions of electrified bodies, or electrostatic capacities, in an electrostatic system.