The author of this paper, after some preliminary observations, arranged his remarks under the following heads:—1. On the food and sex of the Vendace of Lochmaben. 2. On the food of the Herring (Clupea Harengus, Lin.) And, 3, On the food of the Salmon (Salmo salar, Lin.)

1. As to the food of the Vendace (Coregonus Lavaretus, Fleming), he observed, that fishes in lakes, and feeding on animal food, must necessarily subsist on the small aquatic animals found in these lakes: That there is no reasonable analogy between the vendace and the herring, because they live in different mediums, the one in salt, the other in fresh water; and that their food cannot, therefore, be the same, none of the animals upon which fishes feed being common to both: That, besides, they are of different natural families: That writers on natural history state the animalcules which are found in the stomach of the vendace, and the other minute animals found in lakes, to form the food of fresh-water fishes generally; and that Leeuwenhoeck had even figured the identical animal found in the stomach of the vendace in 1833 more than 130 years before, stating that it and the other minute animals in similar localities, formed the food of the larger fishes.

These caves, which were first described by the present Bishop of Norwich in 1832, and have since been more fully explored by Dr cumming of Denbigh, were visited by the author in the autumn of 1837. The principal cave is a fissure in a grand mural escarpment of the mountain limestone of Wales, about two miles and a-half south-west of St Asaph, and occurs half-way down the precipice, which seems to be about 250 feet in height. It forms at that point the southern boundary of the limestone, which constitutes the basis of the Vale of Clwyd; and is divided from the extensive greywacke slate formation of that county by the narrow picturesque Vale of Cyffredin, through which the river Elwy flows.

The author of this paper had formerly made experiments on the growth of the salmon fry, by procuring spawn from the river bed where it had been deposited by the salmon. Not considering these experiments, however, as entirely unobjectionable, he procured two fishes from the river Nith in the act of spawning; and having expressed the ova of the female in a convenient place, the milt of the male fish was made to impregnate them as nearly as possible in imitation of the natural process. The ova were then placed in ponds prepared for the purpose, and so arranged as to exclude all chances of error as to the species, or the nature of the progeny. The ponds were two in number;—one twenty-five by eighteen feet,—the other fifty by thirty feet, and two feet deep. The bottom was thickly imbedded with gravel, and a small stream of springwater entered the ponds at the upper corner, and escaped by openings at the other end.

Under the title Terrestrial Mechanism of the Tides, the author of this paper means to include the consideration of those causes which regulate the propagation of the tides, so as to exclude entirely the examination of the mechanism by which they are primarily produced. The generation of the tidal elevation in the Pacific or Atlantic Ocean is a question entirely of celestial mechanics. But the tides, after having been generated by solar and lunar attraction in a manner that is found to be perfectly in accordance with the varying intensities of these forces, do not subside at the instant when these forces cease to act, but continue to exist during a long period of time, reaching our shores three days after their birth and have obeyed, during this long interval, laws perfectly independent of the original influence by which they were produced, and presented phenomena in direct opposition to it. They have obeyed the laws of terrestrial hydrodynamics. The law of the propagation of the tidal wave through the ocean and around our shores, belongs therefore to terrestrial, not to celestial mechanics.

James's Powder is a patent nostrum, which has been in use for upwards of a century as a febrifuge. It was avowed by its inventor to contain antimony; but, as its mode of preparation was kept secret, the exact state in which the antimony existed in the powder was not known. The composition of James's Powder was first examined by Dr George Pearson, who published his experiments in the eighty-first volume of the Philosophical Transactions. He believed it to consist of 43 per cent. of phosphate of lime, and 57 of peroxide of antimony M. Chenevix, in the Phil. Trans. for 1801 gave an account of some experiments which he had made on James's Powder, by which he found it to contain only 44 per cent. of the oxide of antimony. Berzelius, in his Lehrbuch, gives an account of an examination which he had made of a specimen of the powder. He found that about two per cent. was soluble in water, and this he found to consist of antimonite of lime.

The author commenced his memoir by observing, that about two years ago, he read to the Society some observations respecting an entozoon, of a very singular nature, occurring amongst the human muscles, a species of minute, and indeed microscopic, vibrio. The merit of the discovery was due to Messrs Hilton and Paget of London. Dr Farre afterwards gave an account of its internal structure. Soon afterwards it was announced, that this peculiar entozoon had occurred in other dissecting rooms—in Bristol, for example, and in Dublin. It was added, that the occurrence was rather frequent, in Dublin particularly, and that its existence amongst the human muscles seemed traceable to previous debility and exhaustion of the person before death had occurred. The author of the present memoir is, however, of opinion, that neither of these points has been made out clearly.

The object of this paper was the refutation of certain arguments brought forward against the doctrine of Isomorphism, more especially by those who allow the existence of an approach to, although they deny absolute identity of, form.

The author sets out by shewing, that most of the arguments are deduced from observations made on crystallized minerals; and he then proceeds to state the many important circumstances which tend to influence the form of these bodies, but which can be easily avoided in those salts which admit of being formed artificially; such are, the intense temperature to which they are subjected, the pressure of surrounding matter, the admixture of foreign bodies, &c. each and all of which he proves to exert a powerful influence over the forms of crystals.

The parallelogram which formed the subject of this communication is the rectangle whose sides are to each other in the ratio of the diagonal of a square to its side,—a figure well known to architects, sculptors, and painters, from its beauty, and frequently adopted in the practical arts.

The author shewed that if the given rectangle be bisected by a line parallel to its shortest side, each segment will be a figure similar in all respects to the original rectangle; and if either of these halves be itself bisected in the same manner, their halves will be rectangles similar to the original rectangle; and so on ad infinitum. The sides of the primary figure and its halves are continual proportionals, represented by the series

The author endeavours to trace an analogy between the properties of this parallelogram and the logarithmic spiral.

The author was led to the investigation of this subject by its connection with that branch of Medical Jurisprudence which treats of the prevention and detection of forgery.

It is well known that common writing-ink maybe totally effaced from paper by certain chemical agents, and that several others so impair its colour, that the characters traced with it become illegible. To the first class of chemical agents belong chlorine, and substances containing it, as well as oxalic acid; to the second diluted solutions, or the vapours of the mineral acids, and of the caustic alkalis. These agents were applied to written specimens of a great number of different inks, and the degree of resistance to their effects was considered as the criterion of the durability of each.

The author commenced his communication by stating, that he should divide his memoir into two parts, the first being devoted to a mere narrative of facts, the second to explanations of these facts.

In describing the geological features of the district, he noticed first the stratified or rudimentary rocks, and next the unstratified rocks.

The STRATIFIED consist of sandstone, shales, limestones, coal, and clays; which rocks seemed severally to abound or prevail, in the order now stated.

“A series of delicate and tedious experiments on heat have conducted me to the following results, which will be fully discussed in a paper shortly to be laid before the Society.

“1. An entire confirmation of my previous statement, that different kinds of heat are differently susceptible of polarization by transmission through a given bundle of mica plates; heat from obscure sources being less polarizable than that from luminous sources. I considered my investigations incomplete until I had proved not only that my former experiments had led me to correct results, but also why the only other person who I believe has attempted to obtain them was led to the opposite conclusion, as stated by M. Melloni in the Annales de Chimie for May 1837, namely, that all kinds of heat are equally susceptible of polarization. I have at length discovered, in the description of M. Melloni's method, the cause of his failure to detect this fact.

It was stated by Dr Parnell, that in Lochlomond are found two species of Coregonus, one of which he believes to be an undescribed species, and the other, which was first noticed by Lacépède under the name of Coregonus Clupeoide, has been confounded by British naturalists with the Coregonus Laveretus, or Ulswater Gwyniard.

From Lacépède's short and imperfect description of the Coregonus Clupeoide of Lochlomond, and as two species are now found inhabiting the same locality, it is impossible to state with a certainty as to which of the species he alludes; therefore the name of Coregonus Lacepedei was proposed for the one species, and that of Coregonus microcephalus for the other, as illustrative of the species.

This part of the memoir was devoted exclusively to an attempt to explain or account for the facts described in the first part of the memoir.

The geological epoch when the strata composing the coal-measures of this district were deposited, was first noticed. It was stated that these coal-measures were deposited at a period immediately following the deposition of the old red sandstone formation; and that this older formation was to be seen both on the north and on the south sides of the Lammermuir Hills, dipping under the coalmeasures, and resting on the upturned greywacke strata of these hills. The lowest member of the old red sandstone group is a coarse conglomerate, evidently formed by the denudation of these greywacke hills; and the uppermost members consist of soft argillaceous sandstone, of a deep red colour.

The object of the author was to lay before the Society the result of an investigation into the state of the air usually respired in public buildings in this country and on the continent, to shew that the amount of air usually allowed for respiration is far below what is necessary to sustain the system in a healthy tone, and to give an account of the various experiments and observations upon which this opinion was founded.

He entered also into an examination of the method that ought to be adopted in introducing and regulating the supply in different apartments.

The author states that the Fur Seal merits attention in a commercial as well as a scientific point of view. The South Sea Seal trade, though comparatively of recent origin, has been prosecuted to a much greater extent than the northern; and especially in pursuit of two species of seals,—the Proboscis Seal, or Sea Elephant, for its oil, and the Fur Seal, for its skin.

After some preliminary remarks upon the nature of the coats or robes of seals, the author, in the absence of scientific information concerning the fur-seal, turns to the works of navigators and seal-hunters, and finds distinct allusion made to it in the writings of Cook, Clayton, and especially of Mr Weddell, who commanded several expeditions undertaken chiefly for its capture.

In this memoir, the author endeavours to trace the antiquity of the white oxen of Cadzou and of Tankerville during the historic period of Britain, but thinks that materials are altogether wanting for such an inquiry. No records exist in proof of these cattle being aboriginal; or, if introduced into the island by any of the three great races of men found in it, it would be difficult to offer a conjecture by which race they were introduced. Had the cattle of Britain been generally white in Caesar's time, it is probable that that great man would have noticed the fact.