tainty acquired that the food does not enter there, but on the contrary that they are found full of bilious liquor, has induced M. de Serres to conclude that they are reservoirs of that humor.

He deprives the grasshoppers, and the analogous genera, of the quality of ruminating animals, which had been ascribed to them, and he has convinced himself that these animals do not bring the food back to the mouth; but that they throw out only in certain circumstances this biliary juice, of which they have so great a quantity. This long memoir contains many other curious observations on the form of the intestinal canal, the proportions of its parts, and their relation to the disposition of insects. We shall speak of it with detail in our next year's analysis.

M. Dutrochet, physician at Chateau-Renaud, department of the Indre, has made a curious observation on the gestation of the viper. He assures us that the young vipers have their umbilical vessels distributed not only on the yoke of the egg, in which they are at first enclosed, but that a part of these vessels is distributed likewise on the internal surface of the oviducts, and forms a net which may be considered as a real placenta. The vipers in that case would participate in the mode of nutrition peculiar to the mammalia, and in that hitherto conceived to belong exclusively to the whole class of oviparous animals.

(To be continued,)

ARTICLE XIV.

SCIENTIFIC INTELLIGENCE; AND NOTICES OF SUBJECTS CONNECTED WITH SCIENCE.

I. Lectures.

The following arrangements have been made for lectures, at the Surrey Institution, in the ensuing season :-Mr. 1. Mason Good, on the Philosophy of Physics; to commence on Friday, the 5th of November, and to be continued on each succeeding Friday. Dr. Thomson, on Chemistry; to commence on Tuesday, the 9th of November, and to be continued on each succeeding Tuesday.-Mr. Bakewell, on Natural and Experimental Philosophy; to commence early in January, 1814.—Dr. Crotch, on Music; early in February, 1814.

William Thomas Brande, F. R.S. Prof. Chem. R. I. will commence his course of Lectures on Chemical Philosophy at the Theatre of Anatomy, Windmill-street, on the second Tuesday, in October, at nine in the morning. They will be continued every Tuesday, Thursday, and Saturday, throughout the season,

and will terminate in May. The course is divided into the five following parts-1. Of the Powers and Properties of Matter, and the General Laws of Chemical Changes. 2. Undecompounded Substances, and their mutual Combinations. 3. Vegetable Chemistry, 4. Animal Chemistry. 5. Geology.

Middlesex Hospital.-The Autumnal Course of Lectures on Midwifery, delivered by Dr. Merriman, Physician-Accoucheur to this Hospital, and to the Westminster General Dispensary, will commence October 11th, at half-past ten o'clock.

On Monday, October 4, a Course of Lectures on Physic and Chemistry will commence, at No. 9, George-street: On the Therapeutics and Practice of Physic, from eight till nine; and the Chemistry from nine till ten. By George Pearson, M.D. FR.S. A Register is kept of the Cases of Patients in St. George's Hospital, and a Clinical Lecture is delivered every Saturday morning, at nine o'clock.

Mr. T. J. Pettigrew will commence a course of Lectures on Human Anatomy and Physiology, on Wednesday, the 20th of October. The course, to be comprised in 12 Lectures, will be delivered on Wednesday and Friday evenings, at eight o'clock precisely. The Introductory Lecture will consist of a General View of the Animal Structure, to which there will be free admission. Particulars respecting the Lectures may be obtained by application to the Lecturer, No 3, Polt-court, Fleet-street.

Dr. Prout intends, in the course of the winter, to deliver a series of Lectures on Animal Chemistry. The object of these Lectures will be to give a connected view of all the principal facts belonging to this department of chemistry, and to apply them, as far as the present state of our knowledge will permit, to the explanation of the phenomena of organic actions.

Dr. Thomson proposes next winter to give a Practical Course of Chemistry to a very limited number of young Gentlemen, who will reside in his house during its continuance. The Course will begin on the 1st of January, 1814.

II. New Example of Combustion during Combination.

It is well known that when sulphur is, made to combine with copper, iron, and some other metals, previously reduced to powder, and well mixed, the compound becomes red hot, and glows like a live coa! just at the instant of its formation. The same thing takes place when phosphorus is made to unite with lime, barytes, and strontian. When quicklime is slacked in obscurity, it frequently becomes luminous; and there is little doubt that the saine thing would happen to barytes and strontian. Chevreul has lately observed that when barytes or strontian is heated in contact with muriatic acid gas, the gas is absorbed, and the earthy salt formed becomes red-hot. There can be little

doubt that this evolution of heat is owing to the condensation of the gas. It is true that in the present case the agency of oxygen is not excluded; for if we adopt the opinion of Davy respecting the composition of muriatic acid, it is obvious that in the present case a double decomposition takes place. The chlorine of the muriatic acid unites with the metallic basis of the barytes, and forms barytane, while the hydrogen of the muriatic acid combines with the oxygen of the barytes, and forms water; but if we consider that both muriatic acid and barytes are products of combustion, it will be obvious that the presence of the oxygen alone cannot account for the light and heat evolved.

III. Camphoric Acid.

Camphoric acid was discovered by Kosegarten, and afterwards examined by Bouillon Lagrange. Bucholz has lately published the result of his experiments on this acid, which, from the known precision of this chemist, deserve to be stated here.

Camphoric acid is white, and assumes the form of feathershaped crystals. Its taste is acid, and it leaves an impression of bitterness upon the palate. It dissolves in 100 times its weight of cold water, and in 11 times its weight of boiling water. 100 parts of cold alcohol dissolve 16 of camphoric acid. Boiling alcohol is capable of dissolving any quantity of it whatever. When camphoric acid is sublimed, it is partly decomposed, and the sublimed portion refuses to crystallize. 50 grains of camphoric acid require for saturation 28 grains of carbonate of lime (or 157 grains of lime). The camphorate of lime has an excess of acid, and crystallizes so irregularly that the shape of the crystals could not be determined. Its taste is somewhat similar to that of lime, and not the least saline. When heated it does not melt, but is converted into carbonate of lime. 100 parts of cold water dissolve 216 of this camphorate.

The camphorate of potash may be obtained in prismatic crystals by concentrating the solution, and setting it aside for spontaneous crystallization. Its taste is aromatic and bitter. When heated it melts in its water of crystallization.

IV. Church Steeple of Greenwich.

In consequence of a letter from a correspondent, I was induced to make some inquiry relative to the accident which befel the church steeple of Greenwich some months ago; but the information received exhibited no novelty. The steeple was struck with lightning, and the uppermost part of it, 14 feet in length, was thrown down. It appears that a bar of iron passed from the top of the steeple 14 feet down. Where it terminated, the mischief commenced. The lightning, in making its way down, had torn the building in that place. It got afterwards to some wires connected with the bell, which were melted.

V. Ulmin.

Professor Berzelius informs me, in a letter which I lately received from him, that ulmin is a vegetable substance, not confined to the genus ulmus, but that it forms a constituent part of the barks of almost all trees. He found it in the bark of the cinchona officinalis (Jesuit's bark), and in that of the pinus sylvestris (Scotch fir). It cannot be discovered by the usual mode of analysing bark; because, when the bark is disgested in hot water, the ulmin combines with the tannin of the bark, and can be no longer recognised as a peculiar substance. If we begin the analysis by digesting the bark in alcohol, and afterwards in cold water, the ulmin remains undissolved, and may be afterwards obtained by means of hot water, especially if that water holds a little alkaline carbonate in solution. The properties which I found the substance thus obtained to possess agree nearly with those which you assign to ulmin. "If," says Dr. Berzelius," you think this subject of any importance, I have no doubt that my friend Dr. Young will communicate to you the details of my comparative analyses of these two barks, which you will probably find interesting in other respects besides in those particulars which relate to ulmin."

VI. Oxides of Gold.

Professor Berzelius has favoured me with the following observations on the account of the oxides of gold which appeared inthe second Number of the Annals of Philosophy-" In your account of the oxides of gold you have done me the honour to quote my Manual of Chemistry on the subject. Though I am much flattered by the circumstance, I must take the liberty to observe, that the numbers which you have quoted as mine have been inaccurately quoted. In my Manual I have said that 100 parts of gold combine with 4 and with 12 of oxygen, omitting the fractions. In Davy's Chemistry the result of the same analyses is added as an appendix, but by an error of the press. 11.026 has been printed instead of 4026.-You have given the description of the oxide of gold from Vauquelin. Yet M. Oberkampf, whose dissertation you likewise quote, has proved by decisive experiments that what Vauquelin considered as an oxide of gold is in fact a submuriate. I have verified this assertion of Oberkampf. The oxide of gold is blackish brown, and is obtained by dropping muriate of gold into a solution of caustic potash in water. Towards the end of that article, you draw, as a consequence from the experiments of Oberkampf, that the observation which I have made respecting the ratio of the sulphur in the sulphuret, and the oxygen of the oxide of the same metal, may be rejected as inaccurate in consequence of the want of correspondence between my experiments and his. A small mistake in the translation, it appears, here occasioned an error

on your part. I never made use of the word protoxide, which, though ingenious, does not answer all the purposes of a chemical term. You know perhaps that I divide metallic oxides into suboxides, oxides, and superoxides,* and that the class of suboxides never could be compared with the sulphurets. As to the pretended want of harmony between the sulphuret of gold of Oberkampf and my analysis of the oxide of gold, I beg you to observe that 12.077 (the oxygen that combines with 100 gold) x 2 = 24 154; but Oberkampf found that 100 gold are combined in the sulphuret with 24.39 of sulphur. Hence the experiments agree sufficiently well. If, on the other hand, you mean to say that the suboxide of gold contains only 4 oxygen, and that therefore the sulphuret of gold ought to contain only 8 of sulphur; I must observe, that in decomposing the muriate of the suboxide by hydrosulphuret of potash, we would probably obtain a sulphuret corresponding with the suboxide, just as happens when we decompose in that manner the muriate of the suboxide of mercury.'

"As to

Professor Berzelius concludes his letter as follows:your intention of checking the propensity of chemists to generalize too much, I approve it exceedingly; but request that you will not extend it to the theory of chemical proportions; because it is either general or null. It rather requires to be supported by your credit, since the disposition of chemists appears to me little disposed to acknowledge its truth. I have been publishing memoirs on the subject on the continent for more than three. years, without having hitherto, as far as I know, made a single proselyte. I do not speak of England, where the explanations of Dalton, seconded by Wollaston and by yourself, have begun to acquire some credit."

VII. Alcohol of Sulphur.

My chemical readers will learn with pleasure that the alcohol of sulphur, or sulphuret of carbon, which has of late been made the subject of some curious experiments by Professor Berzelius and Dr. Marcet, is prepared and sold by Mr. William Allen, Plough-court, Lombard-street.

VIII. Gong.

While looking over a set of German Journals, which I lately received from the continent by the way of Sweden, I observed

* I shall take a future opportunity of laying Berzelius's chemical nomenclature before the reader.-T.

I have stated my opinions on this subject at length in the 7th and 8th Numbers of the Annals of Philosophy (pages 32 and 109). Berzelius will there see what the real points are about which we differ in opinion. He will see too that I recognize the agreement which he has here pointed out.-T.