“He stated some interesting facts from veterinary practice. But the principal addition he desired to make was the notice of certain experiments made on the human subject after death, and which Dr Reid repeated and verified.

“A small incision being made in the lower part of the neck, the external jugular vein was found flat; but an incision being made into it on raising the shoulder and clavicle of that side, the vein opened. On holding open the integuments so that the wound might hold fluid, milk was poured into it: the milk remained stationary as in a cup; but on elevating the shoulder and clavicle, the milk descended into the vein and disappeared.

“The author adduced arguments to prove, that the Egyptians were the real masters of the Greeks in the arts of Design. The Greek writers admit that, when their ancestors were barbarous, the Egyptian colonists of Argos and Athens imported with them the arts of a more polished people; that they brought into Greece images of the Gods; and that the most ancient sculptures mentioned by Pausanias and Pliny bore the impress of an Egyptian character; especially the wooden statues ascribed by Pausanias to the elder Dædalus and to Attalus, the celebrated colossal statue of the Amyclæan Apollo, and the lions still existing over the gate of Mycenæ.

“1.The first part of the paper described the number and intensity of the shocks felt between the 3d October 1839 and 13th April 1840, the point (situated near Comrie) from which they emanated, and the distance to which they extended.

“II. The next part of the paper was occupied with an account of the effects, both physical and moral, produced by the shocks.

Under the first class were described the different kinds of injury done to walls, according to their direction, and the nature of the ground on which they were built. Under the second were mentioned the alarm felt by the inhabitants of Strathearn during the great shock of 23d October, as also the quick perception of it by the lower animals, and the terror they evinced at it.

The principles which the study of the Nerves of Sensation and of Voluntary Motion within the Orbit is thought to illustrate, are:—

1. The peculiarity of the muscles of the Eyeball, that they receive few or no sensitive filaments, such as supply all other muscles of the body,—coupled with the peculiarity of their office, that they are designed, in the natural state, to be regulated, not by sensations excited in themselves by their action, but by sensations excited thereby in the Retina,—suggests an important reflection on the use of sensitive nerves and of sensations in guiding and regulating all voluntary and instinctive muscular motion; the sensations which result from the commencing action in every case fixing the effort of the will on the right muscles, and regulating the extent to which the contractions shall be carried; while experience in some cases, and instinct in others, teaches what motor nerves must act, in order to excite the commencement of these sensations.

The subject of Crystalline Reflexion has been treated by Mr MacCullagh and M. Neumann; but both these writers commence their investigations by assuming that certain equations hold true at the common surface of two media. The object of the present Memoir is to obtain such equations from mechanical considerations. To attain this, the following hypotheses are made:—

1. That common light consists of vibrations, whose plane of motion is continually changing without law, or is indeterminate.

2. That light, polarized in a given plane, consists of vibrations perpendicular to that plane.

From a series of experiments made last summer, the author infers, in confirmation of the results obtained by Young, Berard, and Arago, that the chemical rays of light are subject to the same laws of interference and polarization as its luminous rays.

He found that the two images, produced by the sunbeam, and also by its extreme violet rays, when refracted through a calc-spar prism, quickly produce dark impressions, on being thrown upon photogenic paper, and that the extraordinary ray produces more effect than the ordinary one.

The author stated, that besides the original localities at Skaill, Ichthyolites have been found at Breckness, Quoyloo, and Kirkwall, in Pomona, in South Ronaldshay, and in Papa-Westray. The species already recognised from these localities are, 1. Osteolepis macrolepidotus. 2. Osteolepis microlepidotus. 3. Cheirolepis Traillii. 4. Cheiracanthus minor. 5. Diplocanthus crassissimus. 6. Dipterus macrolepidotus. 7. Platygnattus paucidens. 8. Coccosteus latus. 9. Plerichthys Milleri. 10. Diplopterus Agassiz.

The object of the author in this part of his investigation, is to shew that the portion of the food of plants which they receive from the soil, and which he endeavours to prove is chemically combined with it,—although to appearance generically the same in all soils,—is not composed, as some imagine, of one single proximate principle, the same in all circumstances, but consists of several principles varying in their respective proportions in different soils. And he farther attempts to establish the general proposition, that the varying proportion of these principles may be one great cause of the relative fitness of different kinds of soil for the cultivation or nourishment of different kinds of vegetables.

The advantages of registering earthquake shocks were first briefly noticed. 1. Such registers would shew whether, as supposed, the shocks were more frequent and violent during certain states of weather, and particular months of the year. If this were ascertained, some light would be thrown on the cause of the shocks, in so far at least that it must be a cause which can be affected by atmospheric influences. 2. They would serve to shew whether the shocks that occur in this country coincide in time with those occurring in distant countries, and whether therefore they all originate from a common source, or are otherwise connected.

The second part of Dr Alison's paper treated, first, of the inferences which may be drawn from the study of the Nerves of the Eyeball, touching the use of the Ganglia of the Sympathetic Nerve, which are now generally admitted to have essentially the same composition as the ciliary ganglion, i. e. to have motor as well as sensitive filaments from the spinal cord, besides the cords of communication with the other ganglia.

The author commenced by stating, that “in all the specimens he had examined, two circumstances were at once detected; first, That the balls were enclosed, not in the true ivory, but in an abnormal structure; and secondly, that the holes by which the balls entered were either partially or completely cicatrized in cases of wound of the socket; which led him to suppose that, as the tusk is an organ of double growth, the membrane of the follicle and the pulp both play important parts in the process of enclosure, and that there is no regeneration of true ivory,—an hypothesis which was afterwards verified by observation. From a consideration of the opinions of Camper, Blumenbach, Lawrence, and Cuvier, it appeared that doubts are entertained as to the existence of cicatrices after wounds of the tusk, and opinions held as to the impossibility of the occurrence of such phenomena in a non-vascular substance like ivory.

The present memoir is a continuation of that which the author presented to the Society in April 1839. It is divided into four sections. In the first (which is marked Section 4, in continuation of the preceding memoir) the general problem of wave motion is treated of, and the equations to the surface are obtained by two different processes, giving results which agree with those obtained in the former memoir. In the second, the problem of wave motion in a canal of constant width and constant depth in the direction of the width, but of variable depth in the direction of motion, is treated by the method of the variation of parameters. The following are the approximate results:—1. The length of the wave diminishes directly as the depth diminishes. 2. That the velocity of transmission at any point is directly proportional to the square-root of the depth at that point. 3. That, in a channel uniformly and gradually shelving, the whole time of transmission of the wave from end to end, is exactly double what it would be if the depth were uniform; and, 4. That the elevation of the crest of the wave is inversely as the depth of the fluid.

Professor Traill gave an account of the composition of a substance brought under the name of Berg-Meal from Swedish Lapmark by Mr Laing in 1838. It was found just under a bed of decayed mosses, forty miles above Degersfors, in Umea Lapmark. When examined by the microscope, it was found to consist of several species of minute organic remains, which Ehrenberg has considered as the siliceous skeletons of infusoria; the largest measured from 0.006 to 0.0005 of an inch. On analysis, Dr T. obtained 22 per cent, of organic matter, entirely destructible by a red heat; and he found the snow-white residue, which still retained the microscopic forms, to consist of 71.13 of silica, 5.31 alumina, and 0.15 oxide of iron.

Dr Richardson has reduced more carefully the Observations published in the Appendix to Franklin's Second Journey on the Force of Solar Radiation. From observations on a thermometer in the shade compared with those on a thermometer with blackened bulb in the sun, he finds a tolerably regular daily curve of radiation having its maximum at noon. But when (after allowing as far as possible for the disturbing influence of the wind) different months are compared, it is found that in spring the radiation is more intense than in summer after the disappearance of the snow, which Dr Richardson is disposed to attribute to a greater purity in the air at the former period.

The author commenced by alluding to the disposition of geologists to draw conclusions of a general nature too hastily from the facts observed by them, illustrating this remark by referring to the various opinions successively promulgated, not only by geologists generally, but even by the same geological writer, on the subject of the till or boulder clay, the gravel, and sand, by which Great Britain is every where more or less covered. At one period, all these superficial deposits were referred to the action of water alone; now it is the fashion to explain them by the agency of glaciers.

The author began by recapitulating the observations already made known on this subject.

The facts generally admitted (principally on the authority of M. Arago) appear to be, (1.) That a clear sky reflects light polarized in planes passing through the sun, the eye of the observer, and the point of the sky observed, (2.) That this polarization is a maximum in a zone 90° from the sun. (3.) That in the parts of the sky nearly opposite to the sun, this description ceases to be accurate; for the polarization, in a vertical plane passing through the sun and the observer, vanishes at an angle with the sun considerably less than 180°,—perhaps 150° or 160° (varying according to circumstances),—and gradually reappears in a plane perpendicular to the former, at greater angles than this. (4.) That the polarization is more intense in the neighbourhood of the horizon than of the zenith. (5.) M. Babinet has recently remarked that, under certain circumstances, there is a second neutral point in the neighbourhood of the sun.

Since his last communication to the Society, the author has made a variety of experiments, with the view of farther testing the truth of the proposed law which limits the direct action of the voltaic current to the solvent, in solutions of primary elementary combinations in the more important solvents. All his researches have farther confirmed this law in regard to aqueous solutions. Amongst those which he has examined is an aqueous solution of iodic acid as a type of oxyacids; and he found that by connecting such a solution mixed with starch, with a solution of starch in water, by means of asbestus, no iodine was indicated when the starch solution was negative, but was immediately manifested when the iodic solution was negative from the reducing action of hydrogen. In the whole circumstances, he has no hesitation in concluding, “that when aqueous solutions of primary combinations of elementary bodies are submitted to voltaic agency, the dissolved substance is not directly decomposed by the current, but only the solvent.”