Gentlemen,—Of all the agencies which are at work in the material universe, the light of the sun is doubtless the most remarkable, whether we study it in its sanitary, its scientific, or its æsthetical relations In the language of metaphor, it is the very life-blood of nature, without which everything material would fade and perish; the fountain of all our knowledge of the external universe; and the historiographer of the visible creation, recording and transmitting to future ages all that is beautiful and sublime in organic and inorganic nature, and stamping on perennial tablets the hallowed scenes of domestic life, the ever-varying phases of social intercourse and the more exciting scenes of bloodshed and war, which Christians still struggle to reconcile with the obligations of their faith.

The object of this paper was to show the different death-rates which prevailed among the married and unmarried men and women in Scotland.

It was pointed out that the mortality among the unmarried men was, at all ages, very much higher than among the married; that, in fact, the mortality of the unmarried was thrice as high at the age 20 to 25 years; and only slowly approximated to that of the married man at 85 years of age.

Although many able observers have, within the last few years, investigated the physiological action of the Calabar bean, a singular amount of discordance has characterised the results arrived at. An intention, in the first place, of adding proofs in confirmation of the views advanced in an investigation published in 1862, has induced the author to reconsider the subject. The result has been that the actions of this substance have been found to be much more complicated than was at first supposed, and this may be understood when it is stated that it acts on the spinal cord and on the motor nerves, and also on the sympathetic system, and that, in this manner, it directly influences nearly all the vital functions. It is not proposed, at this time, to examine what must be regarded as the most curious action of Physostigma, that, namely, on the pupil, which results from its topical application to the eyeball or to the mucous membranes which are anatomically connected with it. The theories of this action, though some of them have been advanced by men of such eminence as Donders, Graefe, Rosenthal and Bowman, are extremely unsatisfactory. It is hoped that a distinct conception of the general physiological effects will suggest a correct explanation of the myositic action, and there can be no doubt it will assist in arriving at this conclusion.

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.

Dr Hughes Bennett, at the request of the Council, performed several experiments with a view of showing how, in modern times, physiology was successfully investigated by means of newly invented instruments. He noticed especially the subject of animal electricity, stating, that a specimen of the Melapterurus beninensis which had been forwarded to him from Old Calabar in Africa, had been preserved for eighteen months in one of the hot-houses of the Botanic Garden of this city. Unfortunately, it died only that afternoon. He regretted that the arrangements he had made for showing the electrical currents in muscles and nerves had failed, in consequence of the injury which had been inflicted on two of the delicate galvanometers, recently invented by Sir W. Thomson, in their transit from the University to the Society's Rooms. He proceeded, however, to show the influence of continued and interrupted streams of electricity, on muscles and nerves.

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.

In this paper the author described the results of his observations on the presence of the musculus sternalis in upwards of six hundred bodies dissected in the anatomical rooms of the University of Edinburgh. He had found it in nineteen individuals, i.e., in about 3 per cent of the bodies examined. It occurred nearly equally in the two sexes. It bore no relation to the general muscularity of the individual. In eleven subjects the muscle was single, in eight double, making together twenty-seven specimens of the muscle. The variations which it exhibited in its attachments, size, and shape, were then described. In no case were its fibres continuous with those of the rectus abdominis, or were tendinous intersections found in it, but it mostly arose either from the flattened tendon of the external oblique muscle of the abdomen, or from the cartilages of the lower true ribs, and in many instances it was continuous at its upper end with the sternal tendon of one or both sterno-mastoids, whilst in others it was inserted into the aponeurosis covering the pectoralis major. It was always superficial to the great pectoral muscle. Of the single specimens, four occurred on the right side, two on the left; whilst in the remaining five it arose on one side of the middle line, and was inserted either altogether or in part on the opposite side. It formed an excellent illustration of the truth of the general statement, that occasional and rudimentary structures are especially liable to variations in arrangement.

Three or four years ago, wishing to make some experiments on time-keepers, and desiring for that purpose to have a compensation pendulum fitted to my clock, I turned my attention to pendulums composed of two pieces, having different rates of expansion.

Such compensation pendulums are now pretty common; the idea which has led to their construction being this,—that if the pendulum rod be made of material having a very small rate of expansion, and if the bob or weight be of a substance much more expansive, then the upward expansion of the one may be made to compensate for the downward expansion of the other, and so the going of the clock may remain unaffected by changes of temperature.

This paper was in continuation of the series of memoirs on the volcanic rocks of Scotland previously read by the author before the Society, and contained the first portion of the results of a survey of the western region, extending from the south of Antrim to the north of Syke. The districts more especially dwelt upon were the islands of Mull, Eigg, and Staffa. After alluding to the writings of previous geologists upon these tracts, more particularly to the discovery by the Duke of Argyll of tertiary leaves under basalt at Ardtun Head, in Mull, the author remarked that up to this time the great mass of volcanic rocks in the Western Islands has been usually regarded as of Oolitic age—an opinion in which he himself had shared. His object in the present communication was to show that as regards Mull and the adjoining islets this opinion was erroneous, that the enormous volcanic accumulations of these islands belonged in reality to the Miocene period, and that, in all likelihood, the long chain of basaltic masses, extending from the north of Ireland along the west coast of Scotland to the Faroe Islands, and beyond these to Iceland, was all erupted during the same wide interval in the Tertiary periods.

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.

In repeating some of the experiments of Professor Plateau, described in seven interesting memoirs published in “The Transactions of the Belgian Academy,” and in prosecuting his own experiments on the colours of the soap-bubble, the author of this paper observed several new phenomena which may have escaped the notice of the Belgian philosopher.

Professor Plateau has described and drawn the beautiful systems of soap-films, obtained by lifting from a soap solution a cube made of wires about one and a half inch long. This system is a polyhedron, composed of twelve similar films stretching from the wires, and united to a plane quadrangular film in the centre. When this vertical film was blown upon, M. Von Rees observed that it was reduced to a line, and then reproduced in a horizontal position, from which it could be blown again into a vertical position.

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.

The syntheses and oxidation analyses of organic compounds have so confirmed each other in many cases, that chemists are enabled to judge of the structure of a compound from the oxidation products. Many chemists have used the oxidation method in special cases, the bodies operated upon belonging principally to the fatty series; but until Fittig and Beilstein published their memoirs on the aromatic compounds, it was never applied to the systematic study of a hydrocarbon and its derivatives. But although the syntheses and oxidation analyses of the derivatives of benzol confirmed each other, still the structure of the original nucleus (benzol) remained unexplained. Kekulê's original and elegant speculations on the structure of benzol and its derivatives induced me to try the effect of oxidising agents on benzol, with the view of eliciting whether the carbon atoms would separate in the way theory pointed out. The carbon atoms in benzol may be supposed to be arranged in a closed chain, where the carbon affinities are bound two and one alternately.

In this paper chemical substances are represented as “operands,” and chemical processes as “operators”—thus, φ·x is the substance produced by acting on the substance x by the process φ. When φ, χ, ψ, &c., act independently on x, this is indicated by the notation . When they act one on another to produce a complex operator which acts on x, the notation φ·χ·ψ·x is used. It is shown that in the latter case the commutative law does not apply to operators.

Since I described the method of making nitroprussides by the action of nitric acid on yellow prusside of potassium, Hadow (Chem. Soc. Journal, 1866) has given a more productive process, by treating potassic ferridcyanide with an equivalent quantity of mercuric chloride, of sodic nitrite, and of acetic acid. Hadow contends that N2O3 substitutes Cy2 in this reaction, instead of NO as supposed by me. I am still of opinion that the formula of nitroprussides is FeCy5 NOM2. For if an equivalent quantity of an acid be added to a solution of potassic ferridcyanide, and a stream of NO be passed through this solution, at a temperature of between 70° C and 80° C, nitroprusside is slowly but abundantly formed, with the evolution of hydrocyanic acid.

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.