The N. B. All these observations were made at Montauban. window looked towards the west; and the external thermometer fixed in the middle of the window was turned to the north. G. M. I. signifies glass moistened internally. G. R. I., glass running down with moisture internally. G. M. E., G. R. E., G. W. E., the same externally. ARTICLE XII. ANALYSES OF BOOKS. Philosophical Transactions for 1815, Part II. OUR account of this volume will be shorter than usual, as the greater number of the papers which it contains have been noticed in the Account of the Improvements in Physical Science, which occupies the larger part of the last number of the Annals of Philosophy. It will be necessary, therefore, in most cases, merely to refer to the page in our last number containing the abridgment of the paper in question. This part contains the 15 following papers : 1. On some Phenomena of Colours exhibited by thin Plates. By John Knox, Esq. (See Annals of Philosophy, vol. vii. p. 8.) 2. Some further Observations on the Current that often prevails to the westward of the Scilly Islands. By James Rennell, Esq. F.R.S. In the year 1793 Major Rennell published a paper in the Philosophical Transactions pointing out the existence of a north-westerly current setting in between Ushant and the Scilly Islands. In the present paper he states further proofs of the existence of this cur→ rent. He supposes it to be caused by the prevalence of westerly winds, which occasion an easterly current towards Cape Finisterre and Cape Ortegal. This current proceeds along the northern coast of Spain, and assumes a northerly direction when it comes to the coast of France. In consequence of the north-westerly direction of the west coast of France, the current assumes the same direction, and accordingly proceeds from the Saintes and Ushant to the Scilly Islands. The new proofs contained in this paper are the following: 1. The Earl Cornwallis Indiaman, in 1791, being 53 leagues west of Cape Finisterre, experienced an easterly current amounting to 26 miles in 24 hours. 2. A bottle thrown out of a Danish ship situated a little to the north of the Earl Cornwallis was drifted ashore at Cape Ortegal. 3. Admiral Knight, off Cape Ortegal, found the current E. S. E., or nearly along shore, and at the rate of one mile per hour. 4. Admiral Payne being off the Saintes in a severe S.W. gale, was drifted 70 miles north-west. 5. Off Scilly the flood tide runs nine hours northward, but the ebb in the opposite direction only three hours. 6. Joshua Kelly, in his treatise on Navigation, published in 1733, states that an experienced Captain of a West Indiaman being in latitude 48° 30′, and approaching the British Channel, was becalmed for 48 hours, during which he was driven to the northward 46 miles. 7. On the west coast of France the mud is all collected on the north side of the Garonne, &c. and none of it is to be found on the soush side. Major Rennel conceives that a current runs also north along the west coast of Ireland, and after passing the north coast of that island assumes a southerly direction, and proceeds at least further south than Dublin. There is likewise a northerly current along the west coast of Scotland, which proceeds along the north coast, and, assuming a southerly direction, proceeds along the east coast as far as Harwich, where it mixes with the easterly current that flows in the English Channel, and proceeds along the coast of Holland and Jutland to the Naze of Norway. 3. Some Experiments on a solid Compound of Iodine and Oxygen. By Sir H. Davy, LL.D. F.R.S.(See Annals of Philosophy, vol. vii. p. 30.) 4. On the Action of Acids on the Salts usually called Hyper-oxymuriates, and on the Gases produced from them. By Sir H. Davy, LL.D. F.R.S.-(See Annals of Philosophy, vol. vii. p. 28.) 5. Further analytical Experiments relative to the Constitution of the Prussic, of the Ferrureted Chyazic, and of the Sulphureted Chyazic Acids, and to that of their Salts, together with the Application of the Atomic Theory to the analyses of those Bodies. By Robert Porrett, jun. Esq.-Mr. Porrett's analysis of prussic acid appears to have been made with great care, and with sufficient precision. He rated the quantity of hydrogen too high, because he was ignorant of the true nature of cyanodide of mercury. When his numbers are corrected, by attending to the true nature of that body, his results will come sufficiently near those of Gay-Lussac. The sulphureted and ferrureted chyazic acids appear to be distinct substances, and probably Mr. Porrett's views of their constitution are correct. It is obvious that Gay-Lussac formed sulphureted chyazic acid by mixing together cyanogen and sulphureted hydrogen, though he himself was not aware of what he had done. 6. On the Nature and Combination of a newly discovered Vege table Acid, with Observations on Malic Acid, and Suggestions on the State in which Acids may have previously existed in Vegetables. By M. Donovan, Esq.-(See Annals of Philosophy, vol. vii. p. 37.) 7. On the Structure of the Organs of Respiration in Animals which appear to hold an intermediate Place between those of the Class Pisces and the Class Vermes, and in two Genera of the lastmentioned Class. By Sir Everard Home, Bart. V. P. R. S.-(See Annals of Philosophy, vol. vii. p. 69.) 8. On the Mode of Generation of the Lamprey and Myxine. By Sir Everard Home, Bart. V,P.R.S.—(See Annals of Philosophy, vol. vii. p. 69.) 9. On the Multiplication of Images, and the Colours which accompany them, in some Specimens of Calcareous Spar. By David Brewster, LL.D. F.R.S. L. and E.-(See Annals of Philosophy, vol. vii. p. 8.) 10. A Series of Observations of the Satellites of the Georgian Planet, including a Passage through the Node of their Orbits; with an introductory Account of the telescopic Apparatus that has been used on this Occasion, and a final Exposition of some calculated Particulars deduced from the Observations. By Wm. Herschel, LL.D. F. R.S.-(See Annals of Philosophy, vol. vii. p. 2.) 11. An Account of come Experiments with a large Voltaic Battery. By I. G. Children, Esq. F. R.S.-(See Annals of Philosophy, vol. vii. p. 11.) I noticed a mistake in one of the experiments as related in Mr. Children's paper. I have since received a letter from that Gentleman, in which he has had the goodness to give me the correction of the error, which had crept in during the hurry of transcribing. The diameter of the platinum wire, of which eight feet six inches were fused, ought to have been stated, not 0.44 inch, but 0.044 inch. 12. On the Dispersive Power of the Atmosphere, and its Effect on Astronomical Observations. By Stephen Lee, Clerk and Librarian to the Royal Society.-(See Annals of Philosophy, vol. vii. p. 2.) 13. Determination of the North Polar Distances and proper Motion of Thirty Fixed Stars. By John Pond, Esq. Astronomer Royal, F.R.S. (See Annals of Philosophy, vol. vii. p. 2.) 14. An Essay towards the Calculus of Functions. By C. Babbage, Esq.—(See Annals of Philosophy, vol. vii. p. 1.) 15. Some additional Experiments and Observations on the Relation which subsists between the Nervous and Sanguiferous Systems. By A. P. Wilson Philip, Physician in Worcester.-(See Annals of Philosophy, vol. vii. p. 69.) ARTICLE XIII. Proceedings of Philosophical Societies. ROYAL SOCIETY. ON Thursday, Nov. 30, the day of the anniversary meeting of the Society for the election of office-bearers, the Rumford medal was given to Dr. Brewster, for his papers published in the Transactions. The following office bearers were elected for the ensuing year: PRESIDENT-The Right Hon. Sir Joseph Banks, Bart. K. B. SECRETARIES-Wm. Hyde Wollaston, M. D. Taylor Combe, Esq. M. A. TREASURER-Samuel Lysons, Esq. OF THE OLD COUNCIL. Right Hon. Sir Joseph Banks, Bart. Sir Charles Blagden. Samuel Goodenough, Lord Bishop of Carlisle, V. P. Taylor Combe, Esq. Sec. M. A. Davies Giddy, Esq. M. P. Sir Everard Home, Bart. V. P. Samuel Lysons, Esq. Treasurer, V. P. George Earl of Morton, K. T. V. P. John Pond, Esq. Astronomer Royal. Thomas Young, M. D. Sec. For. Corresp. OF THE NEW COUNCIL. John Barrow, Esq. Mark Beaufoy, Esq. Henry Brown, Esq. Sir Humphry Davy. Philip Earl of Hardwicke, K. G. Edward Howard, Esq. John Latham, M. D. Pres. Coll. Phys. Thomas James Mathias, Esq. Sir John Nicol, M. P. George Earl of Winchelsea. K. G. The deaths since last anniversary, including two foreign members, have been 23; the elections about 30. The number of the Society at present is 594, to which must be added 45 foreign members, making a total of 639 members. On Thursday, Dec. 7, a paper by Dr. Reid Clanny was read, giving a further account of his lamp for the security of colliers against the fire-damp. He has now constructed it of such a size that it may be put into the great coat pocket. It may be made of copper for 17. 14s., and of block tin for 17s. A piece of mechanism at a low price is attached to the bellows, capable of supplying the lamp with air for an hour. Dr. Clanny relates a set of trials made in an apartment filled with carbureted hydrogen gas to the exploding point, and in a coal-mine the air of which was in the same state. In both cases the air within the lamp exploded, and the lamp was extinguished, but the external air was not in the least affected. He showed by a set of experiments that by attending to the proper mode of supplying the lamp with air, the candle will continue to burn even when the carbureted hydrogen within the lamp explodes. Dr. Clanny states in this paper that the expense for steel mills in many collieries is much greater than would be requisite to light the mine by means of his lamp. In one mine he says it amounts to 30%. a week. Dr. Clanny likewise gave an account of the numerous explosions that have taken place in the neighbourhood of Newcastle, and of the opposition which he has encountered in attempting to introduce his lamp into the coal-mines in the district in which he resides. On Thursday, Dec. 15, a paper by Mr. Herschel on the functions of exponential quantities was announced; but, from the nature of the subject, could not be read. At the same meeting part of a paper by Dr. Brewster on the properties of heat as modifying the nature of glass was read. He showed that, by heat, plates of glass acquire the properties of all the different kinds of crystallized bodies. One portion depolarizes the ray of light in the same manner as those crystals which attract the extraordinary ray towards the axis; another part in the same manner as those crystals which repel the extraordinary ray from the axis. On Thursday, Dec. 21, Dr. Brewster's paper was continued. A great number of curious facts were detailed; but from the nature of the paper, and the constant reference to figures, it is scarcely possible to form an accurate idea of it merely from hearing it read. He found that by heating glass red hot, and cooling it upon cold iron, it acquired a permanently crystallized texture. Of all the minerals tried, obsidian was the only one whose texture was altered by a moderate heat. This points out a further analogy between obsidian and glass, and renders the opinion of those who consider this mineral as of volcanic origin still more probable. On Thursday, Jan. 11, Dr. Brewster's paper was concluded. He pointed out the analogy between magnetism and heated glass, |