After a short statement of the discovery of paracyanogen by Professor Johnston, and of its leading properties, the author proceeded to shew how, with certain precautions, cyanogen may be converted entirely, or nearly so, into the isomeric form paracyanogen. This he accomplished by exposing bicyanide of mercury suddenly to the temperature most favourable to the production of paracyanogen, which he found to be a low red heat, and employing also pressure, by confining the cyanogen gas which is at first expelled. By these means he succeeded in resolving the salt almost entirely into mercury and paracyanogen, the latter of which amounted in some trials to more than nine-tenths of the cyanogen contained in the bicyanide. The pressure required was not quite two atmospheres, namely 1.74.

This paper is intended to give an account of the more recent researches of the Italian antiquaries and geologists connected with the well-known temple of Jupiter Serapis at Pozzuoli, which have been verified in several particulars by the author, by personal inspection, and extended to other parts of the western coast of Italy, where traces of marine lithophagi have been found at a height, as alleged by Niccolini, of even 250 feet above the present sea-level.

The most interesting modern observations are those of Niccolini on the actual change of relative level of the sea and land, ascertained by a fixed gauge which he has observed frequently between 1823 and 1838. In that time the land appears to have risen through a height of 112 millimetres or 4½ inches; and this change has been progressively and not suddenly effected.

He recommenced with the statement of the difference with which water flowed from a reservoir through tubes of equal calibre, but unequal lengths; and of the effect of pressure on elastic tubes, shewing that the impediment to the transmission of fluid through them was proportioned to their length. He stated that the obstruction at the turn of a tube, was proportioned to the acuteness of the angle. He then inferred that the arteries were in circumstances to render the delivery of blood unequal, unless there was a living property additional to the hydraulic laws.

Then, referring to the effect of capillary attraction, he argued, that if the law prevailed in the animal body as in dead tubes, then, on estimating the length of vessels of capillary size, and the attraction existing between solid and fluid, the circulation could not go on.

The object of this paper is to controvert the generally received opinion, derived from the classical writers, and adopted by most philosophers, that human society, in its original state, was one of savage barbarism; and, that, in the supposed progress from savage to civilized life, three separate stages or gradations have been gone through, the one leading necessarily to the other. These stages,—or the hunter's life, when the food of man was procured by the chase of wild animals, the pastoral state, when flocks and herds formed his chief support, and the agricultural state, when grains were cultivated,—the author shews never had any existence, except in the fancies of poets or the theories of philosophers.

The author of this paper states in it his belief, that the curious fact formerly announced to the Society of the greater permeability of mica, laminated by heat, to heat of low temperature, contrary to the usual character of the same substance (a property which he has since extended (see Proceedings, Jan. 1840) to changes of mechanical conditions of surface), may very probably explain, as M. Melloni anticipates, the difference in point of fact long contested between them as to the equal or unequal polarizability of heat from different sources.

This genus of shells belongs to the Class Gasteropoda of Cuvier, and to the family Turbinacea of Lamarck, of which the general character is to have the shell turreted or conoid, with the aperture rounded or oblong, and the margin disunited.

M. Michelotti was induced to undertake the examination of the fossil Italian species of this genus, from the doubts prevailing regarding the identity of some of the species in the writings of authors. He describes in all ten species, which are found in the neighbourhood of Turin, of which four have not been previously noticed. The four newly described species are Solarium neglectum, S. pulchellum, S. Lyellii, and S. humile. Two of the other species described, viz. S. Stramineum, Lamarck and S. luteum, have their living prototypes,—the first in the Indian and Mediterranean Seas, and the second in the seas of New Holland.

This paper consists of a critical investigation of a recent paper by Mr Darwin upon this subject, and the author's object is to prove that Mr Darwin's views are untenable; and that his own explanation of the appearances in Glen-Roy, given in his paper in the Transactions of this Society, and ascribing them to successive subsidences of a fresh-water lake, is still the only view reconcilable with the facts.

These experiments consisted in a comparison of the visibility of lights from lenses when at rest, and when revolving with such rapidity as to produce an apparently continuous impression on the sense of sight. They were undertaken at the suggestion of Captain Basil Hall, who had himself in the spring of last year made some trials of a similar kind, in the expectation that the eye would be so stimulated by the bright flashes, that not only the almost imperceptible intervals of darkness would have no effect in impairing the visibility of the rapidly recurring flashes, but likewise the eye would actually be stimulated by the contrast of light and darkness, in such a manner that the effect of the rapid series would be greater than that of the same quantity of light equally distributed over the whole horizon by the refracting zones at present used in fixed lights, which only refract the light in the vertical direction, without interfering with its natural horizontal divergence.

This structure, which appears to have escaped the notice of authors on the subject, is a veined or ribboned appearance which pervades the whole ice of many glaciers. The veins or bands are occasioned by the alternation of ice more or less compact; that which is porous approaching to white or whitish green, the denser ice having a bluish tint. The thickness varies from a fraction of an inch to several inches, and the parallelism may be considered as complete through considerable spaces. It extends in more or less complete development from the névé, or uncompacted glacier, down to the inferior termination; and during the greater part of this space, in the case of the lower glacier of the Aar, the bands were parallel to the lofty walls by which the glacier was bounded laterally; their position was generally vertical, but sloping from below upwards and outwards as the distance from the sides of the glacier diminished.

The plan of this instrument was submitted amongst others to a Committee of the British Association appointed to devise means for registering earthquake shocks. A heavy pendulum, suspended from a frame, will evidently have its bob left behind by its inertia when the frame is moved forwards by any concussion. To render such an instrument very sensible, however, the pendulum must be of great length, which presents many inconveniences in practice. The author, therefore, proposed an inverted pendulum, sustained by a steel wire, on the principle of the noddy invented by Mr Hardy, for ascertaining the stability of clock cases, The balance of gravity and elasticity (which act, the former to displace, the latter to redress, the pendulum) may be rendered as nice as we choose, and hence the sensibility of the instrument is wholly independent of its dimensions.

The Committee to whose examination the papers bequeathed to the Royal Society of Edinburgh by the late Baron Hume, has been intrusted, in the view of suggesting what might be the most proper and useful plan for their future disposal, consistently with the peculiar character and functions of the learned body to which they now belong, having proceeded to examine their contents with care, have now to offer, though not without considerable hesitation, the views that have occurred to them.

Independently of some valuable and interesting autographs of Mr David Hume, to be mentioned in the sequel, the important part of this bequest, to which the attention of the Committee has been more particularly directed, consists of a miscellaneous and very broken mass of letters, which may, in general, be described as the Private and Confidential Correspondence of that illustrious philosopher and historian. Of these letters, about one hundred and forty-five are written by Mr Hume; the number of those addressed to him is about five hundred and fifty; making a total of nearly seven hundred letters.

Greenockite has the form of a regular six-sided prism, with pyramidal summits, the faces of the pyramid being inclined 36° 20′ to their base. The pyramids are sometimes truncated on their summit.

The crystallization is often composite.

The index of refraction of Greenockite is 2.6882, corresponding to the middle of the green space, and to the ordinary ray. Hence Greenockite exceeds the Diamond in refractive power, and also chromate of lead, which I had found to surpass the diamond in this respect.

The double refraction of Greenockite is comparatively small, which is not usual in substances of a high refractive power. It is so small, indeed, that owing to its great dispersive power it is exceedingly difficult to separate the two images.

After a short statement of the labours of Yarrell, Couch, Retzius, and Müller, the author gave a detailed description of the structure of Amphioxus, as observed in the dissection of one of two specimens taken by Mr Forbes in the Irish Sea. The abdominal folds, and the anterior and posterior anal fins, were described, and the existence of a fin in front of the anus illustrated by an observation made by Professor Agassiz, of the temporary existence of a similar fin in the embryos of certain fresh-water fishes.

The osseous system presented two divisions,—the true or neuro-skeleton, and the intestinal or splanchno-skeleton. The true skeleton consisted of a chorda dorsalis, equally pointed at both extremities, without the slightest trace of a cranium, and destitute of any of the peripheral vertebral elements, with the exception of a row of cells—germs of interspinous bones and fin-rays —along the base of the dorsal and anal fins.

The author gave, in continuation of a former paper (see Proceedings of the Royal Society of Edinburgh, 3d Dec. 1838), an account of the continued systematic prosecution and annual reduction of the observations of temperature at different depths (3, 6,12, and 24 French feet) below the surface of the ground, in various geological formations near Edinburgh, viz. the trap rock of the Calton Hill, the incoherent sand of the Experimental Garden, and the coal formation sandstone of Craigleith Quarry. The weekly observations at all these stations have been projected into curves, which present the most remarkable concordance of general features for the four years now complete, and give a just confidence in the comparability of the results obtained. The thermometric readings have all been rigorously corrected for the expansion of the alcohol in the tubes; and, starting from these data, the results in the following tables have been obtained, partly by graphical methods, partly by calculation.

He prefaced it by a short sketch of the knowledge which the ancients had of this plant, of its introduction into Europe, and from thence into the American Islands. He endeavoured to shew, from Spanish authorities, that very soon after the discovery of America, the Spaniards carried the sugar-cane, among other useful plants, with them to the West Indies, and sedulously cultivated it; and he considered the speculations of Labat and Lafitau, on the supposed American origin of the cane, as very inconclusive.

Sir George Mackenzie read a paper on the Theory of the Parallel Shelves in the Glens of Lochaber, in which he first noticed the objections to the theories that ascribed the origin of these appearances to fresh-water lakes, the barriers of which had been destroyed at different periods; and to the ordinary action of the sea when the land was at a lower level than at present. The causes supposed to have removed the barriers, in the first case, being violent disruptions, the preservation of level and parallelism is totally inconsistent with such operations.

The objects proposed were—

First, To discover the difference, which the height of Rain-Gauges above the surface makes in the amount of rain received by each gauge.

Second, To try the effect of an Inclined Funnel, which always presents itself towards the wind.

Third, To test the action of a Globular Gauge or Sphere.

Fourth, To investigate whether any and what difference the size of the funnel made in the quantity of rain received.

The author, after referring to the late researches of Mulder, Vogel, Liebig, &c, whose experiments proved the close analogy between albumen, fibrin, and casein, and their almost identity in composition, stated that, in consequence of some experiments he had performed a few years ago, he was led to entertain the idea that all the animal fluids and solids consist of modifications of one and the same prototype animal matter. The following considerations seemed to confirm this opinion.