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 receive 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 Power of the Eye to adjust itself to different Distances, when deprived of the Crystalline Lens. By Everard Home, Esq. F. R. S. page 1 II. The Bakerian Lecture. On the Theory of Light and Colours. By Thomas Young, M. D. F. R. S. Professor of Natural Philosophy in the Royal Institution. p. 12 III. An Analysis of a mineral Substance from North America, containing a Metal hitherto unknown. By Charles Hatchett, Esq. F. R. S. p. 49 IV. A Description of the Anatomy of the Ornithorhynchus paradoxus. By Everard Home, Esq. F. R. S. p. 67 V. On the Independence of the analytical and geometrical Methods of Investigation; and on the Advantages to be derived from their Separation. By Robert Woodhouse, A. M. Fellow of Caius College, Cambridge. Communicated by Joseph Planta, Esq. Sec. R. S. p. 85 VI. Observations and Experiments upon oxygenized and hyper-oxygenized muriatic Acid; and upon some Combinations of the muriatic Acid in its three States. By Richard Chenevix, Esq. F. R. S. and M. R. I. A. p. 126 VII. Experiments and Observations on certain stony and metalline Substances, which at different Times are said to have fallen on the Earth; also on various Kinds of native Iron. By Edward Howard, Esq. F. R. S. p. 168 APPENDIX. Meteorological Journal kept at the Apartments of the Royal Society, by Order of the President and Council. THE President and Council of the Royal Society adjudged, for the year 1801, the Medal on Sir Godfrey Copley's Donation, to Mr. Astley Cooper, for his Papers On the Effects which take place from the Destruction of the Membrana Tympani of the Ear; with an Account of an Operation for the removal of a particular species of Deafness. ERRATA. Page 133, line 2 and 3, for 38,3, read 383. —— 134, — penult. for hyperoxygenized, read oxygenized. CONTENTS. VIII. Observations on the two lately discovered celestial Bodies. By William Herschel, LL. D. F. R. S. p. 213 IX. Description of the Corundum Stone, and its Varieties, commonly known by the Names of Oriental Ruby, Sapphire, &c.; with Observations on some other mineral Substances. By the Count de Bournon, F. R. S. p. 233 X. Analysis of Corundum, and of some of the Substances which accompany it; with Observations on the Affinities which the Earths have been supposed to have for each other, in the humid Way. By Richard Chenevix, Esq. F. R. S. and M. R. I. A. p. 327 XI. Description of the Anatomy of the Ornithorhynchus Hystrix. By Everard Home, Esq. F. R. S. p. 348 XII. A Method of examining refractive and dispersive Powers, by prismatic Reflection. By William Hyde Wollaston, M.D. F. R. S. p. 365 XIII. On the oblique Refraction of Iceland Crystal. By William Hyde Wollaston, M.D. F. R. S. p. 381 XIV. An Account of some Cases of the Production of Colours, not hitherto described. By Thomas Young, M.D. F. R. S. F. L. S. Professor of Natural Philosophy in the Royal Institution. p. 387 XV. On the Composition of Emery. By Smithson Tennant, Esq. F. R. S. p. 398 XVI. Quelques Remarques sur la Chaleur, et sur l’Action des Corps qui l’interceptent. Par P. Prevost, Professeur de Philosophie à Genève, &c. Communicated by Thomas Young, M. D. F. R. S. p. 403 XVII. Of the Rectification of the Conic Sections. By the Rev. John Hellins, B. D. F. R. S. and Vicar of Potter’s-Pury, in Northamptonshire. p. 448 XVIII. Catalogue of 500 new Nebulae, nebulous Stars, planetary Nebulae, and Clusters of Stars; with Remarks on the Construction of the Heavens. By William Herschel, LL. D. F. R. S. p. 477 Presents received by the Royal Society, from November 1801 to July 1802. p. 529 Index. p. 537