In the first part of the paper, the author states that he still maintains the opinion expressed in his published work on respiration, viz., that the quantity of carbonic acid formed in respiration is exactly equal to that of the oxygen consumed; and he enters into a detailed critical analysis of the different experiments recorded by authors on this subject, placing, however, his chief reliance upon those of Berthollet, and of Allen and Pepys, in order to justify his opinion. He also holds the view that the exhalation of carbonic acid and consumption of oxygen are not independent processes, but are the immediate result of the direct union of carbonic and oxygen within the air-cells of the lungs, and he expresses doubts as to the accuracy of the experiments of Edwards, which have by many been held to establish the opposite view.

Mr Young has here taken up the subject of the salmon's growth where it was necessarily left off by Mr Shaw. So far as the earliest or fresh-water state of the fish is concerned, he entirely agrees with the observer just named. He then states the various opinions which prevail regarding the more or less rapid growth of smolts and grilse, and shews by tabular lists (the result of frequently repeated experiments), that the increase in their dimensions is extraordinary so soon as they descend into the salt water.

Mr Milne divided his paper into two parts, the first comprehending a description of the leading geological features of the district; the second containing the inferences of a cosmological character, which the facts related in the first part seemed to warrant.

In describing the geology of Roxburghshire, Mr Milne referred, first, to the stratified rocks; secondly, to the igneous rocks; and, thirdly, to the superficial, or (as they have been sometimes termed) the diluvial deposits.

The charcoal of the pith of the elder consists of plates of extraordinary thinness. It was in examining this charcoal, that the author first observed the property which is the subject of his paper. He detected it by means of the microscope, using a high magnifying power. By analogy, he was led to infer that the power of transmitting light must belong to charcoal in general, in all its varieties, when reduced to the state of fine powder or filaments,—an influence which he found confirmed by experiment in a number of different instances, as the charcoal of the pith of the sycamore, of the pith of the rush, the fibre of cotton, flax, &c. He also found it to belong to lampblack, to cork in very fine powder, to anthracite, and plumbago.

This paper does not admit of abridgment. The author gave an account of a survey which he executed of the whole extent of the principal glacier of Mont Blanc and its tributaries. A base line of nearly 3000 feet was carefully measured in the valley, and extended by means of a very careful triangulation to a point on the glacier distant 28,600 feet, and elevated 4400 above the base line.

This subject is treated under eight different heads:—1. On the law of visible direction in Monocular vision. 2. On the law of visible direction in Binocular vision. 3. On vision of objects of three dimensions, by monocular vision; by binocular vision. 4. On the binocular vision of figures of different magnitudes. 5. On the cause of the perception of objects in relief by the coalescence of dissimilar pictures. 6. On the doctrine of corresponding points. 7. On the vision of cameos and intaglios. 8. On the change in the apparent position of the drawings of solid bodies.

In the first section of the paper, the author described the parts which enter into the structure of the villi of the placenta. The villi are covered by a membrane with which anatomists are already familiar. Within this membrane, and attached to its internal surface, is a layer of cells, which has also been observed, and described as epithelium. The cells composing this layer, Mr Goodsir denominated the external cells of the villus. Th next structure is a membrane not hitherto described, and named by the author the internal membrane of the villus. The adhesion of this membrane to the external cells is so slight, that it is generally seen at some distance from them, even in villi which have undergone no violence.

The author detailed in this paper the methods of observation by which he was enabled to ascertain the daily and even hourly motion of different parts of the glacier.

The following are some of the principal results:—

I. In the particular case of the Mer de Glace, the motion of the higher parts of the glacier are on the whole slower than those of its lower portion, but the motion of the middle region is slower than either.

The author stated that the different lymphatics, as they enter the gland, become deprived of their external tunic, which passes on to the surface of the organ, to assist in forming its capsule. The middle tunic also becomes weaker, and presents the appearance of fibres arranged in the form of arches, which enclose rounded or oval spaces, particularly towards the surface of the gland, and at the angles formed by the anastomosis of one lymphatic with another.

The investigations in this paper were made in order to reduce certain observations on the boiling point of water, made by the author in the Alps, in 1842.

He considered that it has been too generally assumed that the boiling point corresponds to a barometric pressure which expresses the elasticity of steam taken from the usual tables. He, therefore, attempted to deduce the connection of these data by a direct comparison of cases, in which both the barometer and boiling point were noticed by himself. He finds this result, that the pressures increase rigorously in a geometrical ratio, whilst the temperature of the boiling point rises uniformly.

With reference to his former paper of the 27th February, the author stated, that he had received a most satisfactory confirmation of his opinion respecting the motion of glaciers in winter. From observations made by his direction on the Mer de Glace of Chamouni, and in which he places entire confidence, it appears that the ice moved no less than 76 feet between the 12th December 1842 and 17th February 1843, or at the rate of 13½ inches per diem, whilst its mean motion during the summer was 17½ inches.

This paper contains an account of the Thermometric and Hygrometric observations made at the Barbadoes, from May 1841 to January 1842. The instruments were carefully verified and observed; and, during three months, the temperature was ascertained for 18 hours out of the 24. The author thence deduces the form of the daily curve of temperature for that period.

The author has here pursued the same course of experimental enquiry regarding the sea-trout, as that formerly followed in relation to the salmon. Having obtained impregnated ova, from a pair of spawning fish, he conveyed these ova to his experimental ponds. This was on 1st November 1839, and the young were excluded from the egg in 75 days. They resembled salmon of the same age, but were somewhat smaller and paler. They took two years to grow about seven inches, and the majority were then converted into smolts. But about one-fourth did not assume the silvery lustre; and this peculiarity, Mr Shaw thinks, distinguishes a like proportion even in the rivers.

The author commences his paper with a description of two forms of Electric Batteries, which he used in his experiments, and which consisted of bars of antimony and bismuth. One of these, which was chiefly intended for currents excited by solar and astral influences, was so delicate as to make the needle of the galvanometer deflect at right angles, when one end of the battery was exposed to the influence of clear summer's sun; and he therefore considers it a very delicate meteorological instrument. The other form of battery was principally used for thermo-electric currents, from a low flame of gas, or a spirit-lamp.

The author first called the attention of the meeting to the principal facts which he had established in the two memoirs read to the Society in the year 1836. 1st, Of these the most important are, that when acids cause a red colour, and alkalis a green or yellow, in a blue vegetable infusion, they act on different substances;—the acids on erythrogen, and the alkalis on xanthogen. 2dly, That the compound of alkalis and xanthogen is of a yellow colour, and that when a blue infusion is changed to green, it is owing to the gradual intermixture of the newly generated yellow with the original blue.

“There are certain actions of light which may be called negative actions. By this name I mean to indicate a series of new actions, without pretending to enter into any theoretical considerations. In acting upon an iodised plate, common light produces successively different states, which are made manifest by exposing the plate, when taken out of the camera, to the vapours of mercury. If the plate has remained in the camera but a short time, we shall see only the first traces of an image. The parts most strongly affected by the light condense the mercurial vapour only in small quantities. If the light acts during a longer time, the image will appear with more details and more distinctly, the mercurial vapours being condensed more abundantly. By increasing the time of action, the image gains in details, but the parts which have been affected with a strong light condense the mercurial vapours in smaller quantities.