The author gave an account of a new, easy, and economical method of ascertaining the maximum and minimum of the oscillations of the barometer during the absence of the observer. It consists of two tubes, the diagonal and rectangular barometer of the author, fixed in the same frame. A piece of thick iron wire is introduced into the upper part of the former, and a similar piece into the horizontal arm of the latter. These pieces of wire are pushed before the mercurial columns, and when the mercury recedes, they remain behind, like the index in Rutherford's thermometer. That in the diagonal barometer will give the maximum, the wire in the rectangular barometer will indicate the minimum.

A few years ago, this mineral was described as a new species by Sir David Brewster, on account of peculiar optical properties ascertained by himself, and its crystallographic characters, as determined by Mr Haidinger. Berzelius, however, inferred from the analysis of a specimen sent to him by Sir David Brewster, that it is merely a variety of chabazite, its chemical constitution appearing to be, Silica 48, Alumina 20, Lime 8.35, Magnesia 0.4, Potash 0.41, Soda 2.75, Water 19.30. But, from a subsequent explanation, it seemed probable that Berzelius had analyzed not the true levyine, but a mixture of this and chabazite, constituting the specimen which was sent. The author therefore considered it desirable to execute a new analysis of the mineral in question, which he has found to yield the following results:—

The oak described in this paper is believed by the author to have fallen into a small isolated lake, which had been subsequently filled up by the growth of aquatic plants, so as to form a peat-moss, in which the upper part of the tree has been completely preserved, with its bark entire. The tree had grown 500 feet above the level of the sea. The trunk was feet long, without any appearance of root. As it must therefore have been actually even longer, and the remains of other oaks were found near, it must have grown in a wood, probably forming a part of that division of the Caledonian forest, which, previous to the 14th century, covered Avondale and the upper part of Ayrshire. It must have contained; 534 feet of measurable timber. The author conjectures, that the destruction of the forest commenced during the wars of the succession about the year 1300, and the contests between Edward I. and II. and Baliol and Bruce; for a number of silver pennies of the two Edwards had been found in the neighbourhood, but no coins of a laterdate. It is probable that these had been deposited by English soldiers soon before the battle of Bannockburn in 1314.

The author gave a summary of the discoveries which had taken place during the course of the session relative to the ossiferous beds of the basins of the Forth and Clyde. The additional information contained in his paper comprised, in the first place, an account of the older class of strata upon which the carboniferous group of rocks (in which saurian remains had been found) were supposed, in an unconformable position, to rest. Some of these were referred to a system of beds, which geologists consider as of a newer transition class, intermediate to grauwacke schist and coal strata. Thus, it was found that a peculiar hard and gray sandstone, containing mica, and occasionally alternated with siliceous schist,—which in Shetland succeeds to clay-slate; which, near Loch Ness, succeeds to a transition granite; and, on the north of the Tay, to grauwacke schist,—was thrown up on the south of the Forth, near North Berwick, in the form of immense severed beds or fragments, shewing that this transition-rock (an important one in the series of Scottish strata) is to be regarded as in some places fundamental to the coal measures of the district. This older grey sandstone is also alternated, either with aluminous strata of the same general character, or with a hard sandstone of a reddish colour.

In February 1834, a young Whalebone Whale was taken near the Queensferry, in the Frith of Forth. After being exhibited for a short time by the proprietors, it was dissected by the author as carefully as time and circumstances would permit. The term Rorqual is employed throughout this memoir in the sense employed by M. Cuvier, as designating “Whalebone Whales, with longitudinal folds under the throat and chest.” He thinks the present specimen quite distinct, specifically from the “Great Rorqual” (the Balæna boops, jubarte, musculus, &c), and not as M. Cuvier seems to think it, a mere variety. Among other distinctions, the Great Rorqual has 13 dorsal, and 43 lumbar, sacral, and caudal vertebræ; while the individual now under consideration has only 11 of the former, and 36 of the latter. There are, therefore, at least two species of Rorquals inhabiting the North Seas, viz. the Great Rorqual, and the one now under consideration, a specimen of which was described by Fabricius (Balæna rostrata); another dissected by Hunter, and a third casually observed by James Watson, Esq., who sent a drawing of the same to Dr Traill, by whom it was communicated to Mr Scoresby.

It is well known that chemists have usually admitted the existence of two gaseous compounds of phosphorus and hydrogen,—one spontaneously inflammable, the other not so. Of late, Rose of Berlin has ascertained that both gases are identical in composition, and has consequently been led to infer that the existence of two phosphuretted-hydrogens, differing so much in properties, and yet similarly composed, constitutes an example of isomerism among gaseous bodies.

In this paper the author gave an account of a communication received by him from M. Agassiz, Professor of Natural History at Neuchâtel in Switzerland, relative to the remains of fishes which had been discovered in the limestone of Burdiehouse, and which had been submitted to his examination. As many of the fish discovered would be explained in his “Recherches sur les Poissons Fossiles,” an opinion upon a few only was requested.

In this paper the author stated, that although there is sufficient evidence in the mechanical origin and organic contents of the beds (some of them of extraordinary thickness and extent), which form the coal-measures, to prove the pre-existence of much larger tracts of dry land, in connection with each other, than could possibly have been afforded by the older portions of the present countries; such proofs are altogether wanting when we endeavour to restore, in imagination, what might have been the probable extent of that land, the greater part of which may now lie buried beneath the ocean, or have since been covered by more recent deposits. It appears, however, to have been clothed with a luxuriant tropical vegetation, and sufficiently elevated to have given rise to the rivers and torrents, by which the materials for composing the coal strata had been carried down into the lakes or estuaries, where to all appearance they were deposited.

The author first adverted to the discovery, nearly about the same time, of paraffine by Reichenbach and of petvoline by Dr Christison. The former occurred among the products of destructive distillation; the latter was found in the Rangoon petroleum, and they were soon found to be identical. Reichenbach's researches on naphtha were then quoted, by which it appears that that indefatigable observer could not discover, in the kind of naphtha which he examined, any trace either of paraffine, or of any other product of destructive distillation. On the contrary, he found that naphtha to possess the characters of oil of turpentine, a product of vegetable life j and he succeeded in obtaining a precisely similar oil from brown coal by distillation at 212°.

1. In the case of the Sulphates.

That water may act the part of a base in the constitution of certain hydrates of salts and of acids, had been established by the author in the case of the phosphates. The peculiarity of phosphoric acid is its capacity to unite with water as a base in several proportions, while all other acids combine with water as a base in one proportion only, so far as is yet known. By the author's discoveries in regard to phosphoric acid, the ordinary conceptions entertained of the constitution of salts were completely deranged. The salts called biphosphate of soda, phosphate of soda, and subphosphate of soda, were proved to be all tribasic salts. The common idea of a super-salt is inapplicable to any of them.

The First Section of this paper contains an account of a variety of experiments undertaken with the thermo-multiplier of Nobili and Melloni, the instrument exclusively employed in the subsequent researches. By a comparison of its sensibility with that of air-thermometers, the author concludes that one degree of deviation of the needle of the multiplier corresponds to an effect indicated by about one-fiftieth of a centigrade degree on the others. Without increasing the dimensions of the multiplier, by which its sensibility would be impaired, he has been enabled, by an optical contrivance, readily to measure one-tenth of one of its degrees, corresponding to one-five hundredth of a centigrade degree. From an experiment intended to detect the heat of the lunar rays, concentrated by a polyzonal lens, thirty-two inches in diameter, and acting upon this instrument, he concludes that the direct effect of the moon upon an air-thermometer probably does not amount to one-three hundred thousandth part of a centigrade degree.

Since the Author's former communication to the Society, he has analyzed a portion of a tony fin-ray from the limestone belonging to a fossil fish which has been designated by M. Agassiz, Gyracanthus formosus.

The constituents were found to be,

He has also analyzed a portion of the fossil scales embedded in the limestone. These scales belong to a fossil genus of fish, to which the name of Megaliclithys has been given by M. Agassiz, and which is supposed to approach in character to the Lepisosteus, or Lepidosteus of Agassiz.

Dr Traill stated, as the result of a careful examination of the passages in ancient authors, supposed to prove the early use of arches by the Greeks, that we must abandon all hope of solving this disputed point, by a reference to those authors; and he instanced the danger of inferences from such uncertain data, by comparing the description of the Treasury of Minyas, given by Pausanias, with the still remaining kindred edifice, the Treasury of the Atridae at Mycenae. He also noticed the loose sense in which the ancient Greeks employed the terms ϑολος, ψαλις, ‘αψις.

This brief communication stated the results obtained from the examination of the state of the Char which are caught in the Lakes of Cumberland, particularly in relation to their food and habits of living. This subject the Author promised to resume in another paper.

The author first gives a general account of the process of manufacture of cast-iron previous to the recent improvements, stating the quantities of the various materials put into the furnace, namely, of the Ore, the Fuel, and the Flux. He next states the method suggested first by Mr Neilson of Glasgow, and tried at the Clyde Iron-Works, for increasing the product of the furnaces with the same expense of materials, which consists in previously heating the air thrown into the furnace, in order to accelerate combustion. The method is found to produce a vast saving both in the fuel and the flux, although a certain portion of fuel has, of course, to be separately consumed for the purpose of heating the air, which is done by causing it to traverse a recurved pipe placed within a suitable furnace. During the first experiments, in 1830, the air was heated to 300° Fahrenheit. In 1831, Mr Dixon of the Calder Iron-Works thought of substituting raw coal for the coke which had hitherto been employed for fuel, at the same time that the air was still farther heated to 600° Fahrenheit, and with complete success.

This paper contains the results of an extensive series of experiments made upon different kinds of stone, as well as upon iron and upon brick, porcelain, and other artificial substances. The instrument employed was a pyrometer, of a simple construction, capable of determining quantities not greater than of an inch. The length of the substances generally employed was 23 inches. The general result of these experiments is, that the ordinary building materials of stone expand but very little differently from cast-iron, and that, consequently, the mixture of those materials in edifices is not injurious to their durability. The experiments from which the expansibility of the substances was numerically determined, were made between the limits of ordinary atmospheric temperature and that of 212°; steam being introduced for that purpose between the double casing of the instrument.

The author, after noticing the ancient writers who have left us any description of Babylon, mentioned the short accounts of Benjamin of Tudela, of Rauwolf, Pietro della Valle, Pere Emmanuel, Niëbuhr, and Beauchamp, from which little information is to be derived, compared to what may be gathered from a succession of British travellers; among whom, first in point of time and importance, is Claudius James Rich, late British consul at Bagdad, whose steps have been successively followed by Kinneir, Ker Porter, Buckingham, Keppel, and Mignam.

The author was led into the following investigations, from observing that when alcohol, holding a minute quantity of pure caustic potash, as part, in solution, was acted on by a moderate voltaic power, as a small battery of fifty pairs of two-inch plates, evident marks of decomposition were exhibited, by an evolution of gas from the negative pole, and none from the positive. The experiment recalled to the author's recollection a statement made a few years ago by Dr Ritchie (Phil. Trans. 1832), that when alcohol not holding any substance in solution, was acted on by a powerful battery, gas was given off at the negative pole, which Dr Ritchie stated to be olefiant gas.