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 OF VOL. LXXVII. PART I. I. An Account of a new Comet. In a Letter from Miss Caroline Herschel to Charles Blagden, M. D. Sec. R. S. page 1 II. Remarks on the new Comet. In a Letter from William Herschel, LL.D. F. R. S. to Charles Blagden, M. D. Sec. R. S. p. 4 III. Magnetical Experiments and Observations. By Mr. Tiberius Cavallo, F. R. S. p. 6 IV. Description of a new Electrometer. In a Letter from the Rev. Abraham Bennet, M. A. to the Rev. Joseph Priestley, LL.D. F. R. S. p. 26 V. Appendix to the Description of a new Electrometer. In a Letter from the Rev. Abraham Bennet, M. A. to Charles Blagden, M. D. Sec. R. S. p. 32 VI. Some Account of an Earthquake felt in the Northern Part of England. In a Letter from Samuel More, Esq. to Sir Joseph Banks, Bart. P. R. S. p. 35 VII. Determination of the Heliocentric Longitude of the descending Node of Saturn. By Thomas Bugge, Professor of Astronomy CONTENTS. Astronomy in the University of Copenhagen; communicated by Sir Joseph Banks, Bart. P. R. S. p. 37 VIII. Description of a Set of Halo's and Parhelia, seen in the Year 1771, in North-America. By Alexander Baxter, Esq.; communicated by Sir Joseph Banks, Bart. P. R. S. p. 44 IX. Observations of the Transit of Mercury, May 4, 1786, at Dresden. By M. Köhler, Inspector of the Mathematical Repository of the Elector of Saxony; communicated by the Count de Brühl, F. R. S. p. 47 X. Observations of the Transit of Mercury at St. Petersburg. In a Letter from M. Rumovski, Astronomer in the Imperial Academy, to Mr. J. H. de Magellan, F. R. S. p. 48 XI. An Account of the Strata observed in sinking for Water at Boston, in Lincolnshire. By Mr. James Limbird, Surveyor to the Corporation; communicated by Sir Joseph Banks, Bart. P. R. S. p. 50 XII. Observations of Miss Herschel's Comet, in August and September, 1786. By the Rev. Francis Wollaston, LL.B. F. R. S. p. 55 XIII. An Account of a Thunder-storm in Scotland; with some Meteorological Observations. In a Letter from Patrick Brydone, Esq. F. R. S. to Sir Joseph Banks, Bart. P. R. S. p. 61 XIV. On finding the Values of Algebraical Quantities by converging Serieses, and demonstrating and extending Propositions given by Pappus and others. By Edward Waring, M.D. F. R. S. Professor of Mathematics at Cambridge. p. 71 XV. Experiments on the Production of Dephlogisticated Air from Water with various Substances. In a Letter from Sir Benjamin Thompson, Knt. F. R. S. to Sir Joseph Banks, Bart. P. R. S. p. 84 XVI. An Account of the Discovery of Two Satellites revolving round the Georgian Planet. By William Herschel, LL.D. F. R. S. p. 125 XVII. Remarks on Mr. Brydone's Account of a remarkable Thunder-storm in Scotland. By the Right Honourable Charles Earl Stanhope, F. R. S. p. 130 XVIII. Concerning the Latitude and Longitude of the Royal Observatory at Greenwich; with Remarks on a Memorial of the late M. Cassini de Thury. By the Rev. Nevil Maskelyne, D. D. F. R. S. and Astronomer Royal. p. 151 XIX. An Account of the Mode proposed to be followed in determining the relative Situation of the Royal Observatories of Greenwich and Paris. By Major-General William Roy, F. R. S. and A. S. p. 188 XX. Account of Three Volcanos in the Moon. By William Herschel, LL.D.; communicated by Sir Joseph Banks, Bart. P. R. S. p. 229 CONTENTS OF VOL. LXXVII. PART II. XXI. An Experiment to determine the Effect of extirpating one Ovarium upon the Number of Young produced. By John Hunter, Esq. F. R. S. page 233 XXII. Experiments made to determine the positive and relative Quantities of Moisture absorbed from the Atmosphere by various Substances, under similar Circumstances. By Sir Benjamin Thompson, Knt. F. R. S.; communicated by Charles Blagden, M. D. Sec. R. S. p. 240 XXIII. The Principles and Illustration of an advantageous Method of arranging the Differences of Logarithms, on lines graduated for the Purpose of Computation. By Mr. William Nicholson; communicated by Sir Joseph Banks, Bart. P. R. S. p. 246 XXIV. Observations tending to shew that the Wolf, Jackal, and Dog, are all of the same Species. By John Hunter, Esq. F. R. S. p. 253 XXV. Experiments on the Congelation of the Vitriolic Acid. By James Keir, Esq. F. R. S.; communicated by Henry Cavendish, Esq. F. R. S. p. 267 XXVI. An XXVI. An Account of some new Experiments on the Production of artificial Cold. In a Letter from Thomas Beddoes, M. D. to Sir Joseph Banks, Bart. P. R. S. p. 282 XXVII. An Account of a Doubler of Electricity, or a Machine by which the least conceivable Quantity of positive or negative Electricity may be continually doubled, till it becomes perceptible by common Electrometers, or visible in Sparks. By the Rev. Abraham Bennet, M. A.; communicated by the Rev. Richard Kaye, LL.D. F. R. S. p. 288 XXVIII. Some Particulars relative to the Production of Borax. In a Letter from William Blane, Esq. to Gilbert Blane, M. D. F. R. S. p. 297 XXIX. A Letter from the Father Prefect of the Mission in Thibet, F. Joseph da Rovato, containing some Observations relative to Borax. Communicated by Sir Joseph Banks, Bart. P. R. S. p. 301 XXX. Sur les Gas Hépatiques: par Monsieur Hasselratz. Communicated by Sir Joseph Banks, Bart. P. R. S. p. 305 XXXI. Botanical Description of the Benjamin Tree of Sumatra. By Jonas Dryander, M. A. Libr. R. S. and Member of the Royal Academy of Sciences at Stockholm; communicated by Sir Joseph Banks, Bart. P. R. S. p. 307 XXXII. An Account of an Experiment on Heat. By George Fordyce, M. D. F. R. S. In a Letter to Sir Joseph Banks, Bart. P. R. S. p. 310 XXXIII. Account of an Observation of the Right Ascension and Declination of Mercury out of the Meridian, near his greatest Elongation, Sept. 1786, made by Mr. John Smeaton, F. R. S. with an Equatorial Micrometer, of his own Invention and Workmanship; accompanied with an Investigation of a Method of allowing for Refraction in such Kind of Observations; com- XXXIV. A remarkable Case of numerous Births, with Observations. By Maxwell Garthshore, M.D. F.R.S. and A.S. in a Letter to Sir Joseph Banks, Bart. P.R.S. p. 344 XXXV. Chloranthus, a new Genus of Plants, described by Olof Swartz, M.D. Communicated by Sir Joseph Banks, Bart. P.R.S. p. 359 XXXVI. On the Precession of the Equinoxes. By the Rev. Samuel Vince, M.A. F.R.S. p. 363 XXXVII. Abstract of a Register of the Barometer, Thermometer, and Rain at Lyndon in Rutland, in 1786. By Thomas Barker, Esq. Also of the Rain at South-Lambeth, in Surrey; and at Selbourn and Fyfield, Hampshire. Communicated by Thomas White, Esq. F.R.S. p. 368 XXXVIII. Observations on the Structure and Oeconomy of Whales. By John Hunter, Esq. F.R.S.; communicated by Sir Joseph Banks, Bart. P.R.S. p. 371 XXXIX. Some Observations on ancient Inks, with the Proposal of a new Method of recovering the Legibility of decayed Writings. By Charles Blagden, M.D. Sec. R.S. and F.A.S. p. 451 Presents made to the Royal Society. p. 458 APPENDIX. A Supplement to Major-General Roy's Account of the Mode proposed to be followed in determining the relative Situation of the Royal Observatories of Greenwich and Paris. p. 465 Translation of Father Joseph da Rovato's Letter to the Royal Society, relative to Borax. p. 471