Front Matter

ADVERTISEMENT. The Committee appointed by the Royal Society to direct the publication of the Philosophical Transactions, take this opportunity to acquaint the Public, that it fully appears, as well from the council-books and journals of the Society, as from repeated declarations which have been made in several former Transactions, that the printing of them was always, from time to time, the single act of the respective Secretaries, till the Forty-seventh Volume: the Society, as a Body, never interesting themselves any further in their publication, than by occasionally recommending the revival of them to some of their Secretaries, when, from the particular circumstances of their affairs, the Transactions had happened for any length of time to be intermitted. And this seems principally to have been done with a view to satisfy the Public, that their usual meetings were then continued, for the improvement of knowledge, and benefit of mankind, the great ends of their first institution by the Royal Charters, and which they have ever since steadily pursued. But the Society being of late years greatly enlarged, and their communications more numerous, it was thought advisable that a Committee of their members should be appointed, to reconsider the papers read before them, and select out of them such as they should judge most proper for publication in the future Transactions; which was accordingly done upon the 26th of March, 1752. And the grounds of their choice are, and will continue to be, the importance and singularity of the subjects, or the advantageous manner of treating them; without pretending to answer for the certainty of the facts, or propriety of the reasonings, contained in the several papers so published, which must still rest on the credit or judgment of their respective authors. It is likewise necessary on this occasion to remark, that it is an established rule of the Society, to which they will always adhere, never to give their opinion, as a Body, upon any subject, either of Nature or Art, that comes before them. And therefore the thanks, which are frequently proposed from the Chair, to be given to the authors of such papers as are read at their accustomed meetings, or to the persons through whose hands they received them, are to be considered in no other light than as a matter of civility, in return for the respect shewn to the Society by those communications. The like also is to be said with regard to the several projects, inventions, and curiosities of various kinds, which are often exhibited to the Society; the authors whereof, or those who exhibit them, frequently take the liberty to report, and even to certify in the public newspapers, that they have met with the highest applause and approbation. And therefore it is hoped, that no regard will hereafter be paid to such reports and public notices; which in some instances have been too lightly credited, to the dishonour of the Society. CONTENTS. I. The Croonian Lecture. On the conversion of Pus into granulations or new Flesh. By Sir Everard Home, Bart. V. P. R. S. p. 1 II. On the Laws which regulate the Absorption of polarised light by Doubly Refracting Crystals. By David Brewster, LL.D. F. R. S. Lond. and Edin. In a Letter addressed to the Right Hon. Sir Joseph Banks, Bart. G. C. B. P. R. S. p. 11 III. Observations sur la décomposition de l'amidon à la température atmosphérique par l'action de l'air et de l'eau. Par Théodore de Saussure, Professeur de Minéralogie dans l'Académie de Genève, Correspondant de l'Institut Royal de France, &c. Communicated by Alexander Marcet, M. D. F. R. S. p. 29 IV. On Corpora Lutea. By Sir Everard Home, Bart. V. P. R. S. p. 59 V. Remarks on the probabilities of error in physical observations, and on the density of the earth, considered, especially with regard to the reduction of experiments on the pendulum. In a letter to Capt. Henry Kater, F. R. S. By Thomas Young, M. D. For. Sec. R. S. p. 70 VI. On the anomaly in the variation of the magnetic needle as observed on ship-board. By William Scoresby, jun. Esq. Communicated by the Right Hon. Sir Joseph Banks, Bart. G. C. B. P. R. S. p. 96 VII. On the genus Ocythoë; being an extract of a letter from Thomas Say, Esq. of Philadelphia, to Wm. Elford Leach, M. D. F. R. S. p. 107 VIII. On Irregularities observed in the direction of the Compass Needles of H. M. S. Isabella and Alexander, in their late Voyage of Discovery, and caused by the attraction of the iron contained in the Ships. By Captain Edward Sabine, of the Royal Regiment of Artillery, F. R. S. &c. p. 112 IX. Some observations on the formation of Mists in particular situations. By Sir H. Davy, Bart. F. R. S. V. P. R. I. p. 193 X. Observations on the Dip and Variation of the Magnetic Needle, and on the Intensity of the Magnetic Force; made during the late voyage in search of a North West Passage. By Captain Edward Sabine, of the Royal Regiment of Artillery, F. R. S. and F. L. S. 132 XI. On the action of crystallized surfaces upon light. By David Brewster, LL. D. F. R. S. Lond. and Edin. In a letter addressed to the Right Hon. Sir Joseph Banks, Bart. G. C. B. P. R. S. p. 145 Meteorological Journal for 1818, kept at the Apartments of the Royal Society. The President and Council of the Royal Society adjudged the Medal on Sir Godfrey Copley's Donation, for the year 1818, to Robert Seppings, Esq. for his Papers on the Construction of Ships of War, printed in the Philosophical Transactions; and the Gold and Silver Medals on the Donation of Benjamin Count of Rumford, to David Brewster, LL.D. F.R.S. for his Discoveries relating to the Polarisation of Light. XII. On the specific gravity, and temperature of Sea Waters, in different parts of the Ocean, and in particular seas; with some account of their saline contents. By Alexander Marcet, M.D. F.R.S. &c. p. 161 XIII. An account of the fossil skeleton of the Proteo-saurus. By Sir Everard Home, Bart. V. P. R. S. p. 209 XIV. Reasons for giving the name Proteo-saurus to the fossil skeleton which has been described. By Sir Everard Home, Bart. V. P. R. S. 212 XV. Some Observations on the peculiarity of the Tides between Fairleigh and the North Foreland; with an explanation of the supposed meeting of the Tides near Dungeness. By James Anderson, Captain in the Royal Navy. Communicated by the Right Hon. Sir Joseph Banks, Bart. G.C.B. P.R.S. p. 217 XVI. On the Ova of the different tribes of Opossum and Ornithorhynchus. By Sir Everard Home, Bart.V. P. R. S. p. 234 XVII. The results of Observations made at the Observatory of Trinity College, Dublin, for determining the Obliquity of the Ecliptic, and the Maximum of the Aberration of Light. By the Rev. J. Brinkley, D.D. F.R.S. and M.R.I.A. and Andrew's Professor of Astronomy in the University of Dublin. p. 241 XVIII. On some new Methods of investigating the Sums of several Classes of infinite Series. By Charles Babbage, Esq. A.M. F.R.S. p. 249 XIX. On the optical and physical properties of Tabasheer. By David Brewster, LL.D. F.R.S. Lond. and Edin. In a Letter to the Right Hon. Sir Joseph Banks, Bart. G.C.B. P.R.S. &c. &c. &c. p. 283 XX. An Account of a Membrane in the Eye, now first described. By Arthur Jacob, M.D. Member of the Royal College of Surgeons, Ireland; Demonstrator of Anatomy, and Lecturer on the Diseases of the Eye in the University of Dublin. Communicated by James Macartney, M.D. F.R.S. p. 300 XXI. A new method of solving numerical equations of all orders, by continuous approximation. By W.G. Horner, Esq. Communicated by Davies Gilbert, Esq. F.R.S. p. 308 XXII. An account of experiments for determining the variation in the length of the pendulum vibrating seconds, at the principal stations of the Trigonometrical Survey of Great Britain. By Capt. Henry Kater, F. R. S. - p. 337 List of Presents, - - - - - p. 509 Index.