Front Matter

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 judgement 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 shown to the Society by those communi- cations. 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. The Meteorological Journal hitherto kept by the Assistant Secretary at the Apart- ments of the Royal Society, by order of the President and Council, and published in the Philosophical Transactions, has been discontinued. The Government, on the recommendation of the President and Council, has established at the Royal Obser- vatory at Greenwich, under the superintendence of the Astronomer Royal, a Magnet- ical and Meteorological Observatory, where observations are made on an extended scale, which are regularly published. These, which correspond with the grand scheme of observations now carrying out in different parts of the globe, supersede the necessity of a continuance of the observations made at the Apartments of the Royal Society, which could not be rendered so perfect as was desirable, on account of the imperfections of the locality and the multiplied duties of the observer. A List of Public Institutions and Individuals, entitled to receive a copy of the Philosophical Transactions of each year, on making application for the same directly or through their respective agents, within five years of the date of publication. In the British Dominions. The Queen's Library. The Admiralty Library. The Ashmolean Society, Oxford. The Radcliffe Library, Oxford. The Royal Geographical Society. The United Service Museum. The Royal College of Physicians. The Society of Antiquaries. The Linnean Society. The Royal Institution of Great Britain. The Society for the Encouragement of Arts. The Geological Society. The Horticultural Society. The Royal Astronomical Society. The Royal Asiatic Society. The Royal Society of Literature. The Medical and Chirurgical Society. The London Institution. The Entomological Society of London. The Zoological Society of London. The Institute of British Architects. The Institution of Civil Engineers. The Cambridge University Philosophical Society. The Literary and Philosophical Society, Manchester. The Royal Society of Edinburgh. The Royal Irish Academy. The Royal Dublin Society. The Royal Institution, Swansea. The Asiatic Society at Calcutta. The Royal Artillery Library at Woolwich. The Royal Observatory at Greenwich. The Observatory at Dublin. The Observatory at Armagh. The Library and Museum, Barbadoes. The Observatory at the Cape of Good Hope. The Observatory at Madras. The Observatory at Paramatta. The Observatory at Edinburgh. Denmark. The Royal Society of Sciences at Copenhagen. The Royal Observatory at Altona. France. The Royal Academy of Sciences at Paris. The Royal Academy of Sciences at Toulouse. The Ecole des Mines at Paris. The Geographical Society at Paris. The Entomological Society of France. The Dépôt de la Marine, Paris. The Geological Society of France. The Jardin des Plantes, Paris. Germany. The University at Göttingen. The Cesarean Academy of Naturalists at Bonn. The Observatory at Manheim. The Royal Academy of Sciences at Munich. Italy. The Institute of Sciences at Naples. The Institute of Sciences, Letters and Arts, at Milan. The Italian Society of Sciences at Modena. The Royal Academy of Sciences at Turin. Switzerland. The Société de Phys. et d'Hist. Nat. at Geneva. Belgium. The Royal Academy of Sciences at Brussels. Netherlands. The Royal Institute of Amsterdam. The Batavian Society of Experimental Philosophy at Rotterdam. Spain. The Royal Observatory at Cadiz. Portugal. The Royal Academy of Sciences at Lisbon. Prussia. The Royal Academy of Sciences at Berlin. The Society of Experimental Philosophy, Berlin. Russia. The Imperial Academy of Sciences at St. Petersburg. The Imperial Observatory at Pulkowa. Sweden and Norway. The Royal Academy of Sciences at Stockholm. The Royal Society of Sciences at Drontheim. United States. The American Philosophical Society at Philadelphia. The American Academy of Sciences at Boston. The Library of Harvard College. The Observatory at Washington. The fifty Foreign Members of the Royal Society. A List of Public Institutions and Individuals, entitled to receive a copy of the Astronomical Observations made at the Royal Observatory at Greenwich, on making application for the same directly or through their respective agents, within two years of the date of publication. In the British Dominions. The Queen's Library. The Board of Ordnance. The Royal Society. The Savilian Library, Oxford. The Library of Trinity College, Cambridge. The University of Aberdeen. The University of St. Andrews. The University of Dublin. The University of Edinburgh. The University of Glasgow. The Observatory at Oxford. The Observatory at Cambridge. The Observatory at Dublin. The Observatory at Armagh. The Observatory at the Cape of Good Hope. The Observatory at Paramatta. The Observatory at Madras. The Royal Institution of Great Britain. The Royal Society, Edinburgh. The Observatory, Trevandrum, East Indies. The Astronomical Institution, Edinburgh. The President of the Royal Society. The Lowndes Professor of Astronomy, Cambridge. The Plumian Professor of Astronomy, Cambridge. L. Holland, Esq., London. Sir John William Lubbock, Bart. Captain W. H. Smyth, R.N., Chelsea. Sir James South, Observatory, Kensington. In Foreign Countries. The Royal Academy of Sciences at Berlin. The Royal Academy of Sciences at Paris. The Imperial Academy of Sciences at St. Petersburg. The Royal Academy of Sciences at Stockholm. The Royal Society of Sciences at Upsal. The Board of Longitude of France. The University of Göttingen. The University of Leyden. The Academy of Bologna. The American Academy of Sciences at Boston. The American Philosophical Society at Philadelphia. The Observatory at Altona. The Observatory at Berlin. The Observatory at Breslau. The Observatory at Brussels. The Observatory at Cadiz. The Observatory at Coimbra. The Observatory at Copenhagen. The Observatory at Dorpat. The Observatory at Helsingfors. The Observatory at Königsberg. The Observatory at Manheim. The Observatory at Marseilles. The Observatory at Milan. The Observatory at Munich. The Observatory at Palermo. The Observatory at Paris. The Observatory at Seeberg. The Observatory at Vienna. The Observatory at Tubingen. The Observatory at Turin. The Observatory at Wilna. The Dépôt de la Marine, Paris. The Bowdoin College, United States. The Library of Harvard College. The Waterville College, United States. List of Observatories, Institutions and Individuals, entitled to receive a Copy of the Magnetical and Meteorological Observations made at the Royal Observatory, Greenwich. ### Observatories - Altona . . . . . . M. Schumacher. - Armagh . . . . . Rev. Dr. Robinson. - Berlin . . . . . J. F. Encke. - Bombay . . . . . Dr. Buist. - Barnaoul . . . . . M. Prang, 1st. - Breslau . . . . . Prof. Boguslawski. - Brussels . . . . . A. Quetelet. - Cadiz . . . . . M. Cerquero. - Cairo . . . . . M. Lambert. - Cambridge . . . . Prof. Challis. - Cambridge, United States . . . Prof. Lovering. - Cape of Good Hope . . . T. Maclear, Esq. - Catherineburgh . . . M. Rochkoff. - Christiania . . . M. Hansteen. - Cincinnati . . . Dr. Locke. - Copenhagen . . . M. Oersted. - Dublin . . . . . Sir W. R. Hamilton. - Gotha . - Hammerfest . - Heidelberg . . . M. Tiedemann. - Helsingfors . . . M. Nervander. - Hobarton . . . Lieut. Kay, R.N. - Kasan . . . . . M. Simonoff. - Kew . . . . . Observatory. - Königsberg . - Kremsmünster . . . Prof. Koller. - Leipsic . . . . . Prof. Weber. - Madras . . . . . T. G. Taylor, Esq. - Manheim . - Marburg . . . . . Prof. Gerling. - Milan . . . . . M. Carlini. - Munich . . . . . Dr. Lamont. - Nertchinsk . . . M. Prang, 2nd. - Nikolaieff . . . Dr. Knorre. - Oxford . . . . . M. J. Johnson, Esq. - Paris . . . . . M. Arago. - Pekin . . . . . M. Gachkévitche. - Prague . . . . . M. Kreil. - Pulkowa . . . . M. Struve. - St. Helena . . . Lieut. Strange, R.A. - St. Petersburgh . . . M. Kupffer. - Seeberg . . . . . M. Hansen. - Singapore . . . Lieut. C. M. Elliot. - Sitka . . . . . Messrs. Homann and Ivanoff. - Stockholm . . . . . Prof. Selander. - Teflis . . . . . M. Philadelphine. - Toronto . . . . . Captain Lefroy, R.A. - Trevandrum . . . J. Caldecott, Esq. - Tubingen . - Upsal . . . . . Prof. Svanberg. - Vienna . . . . . C. L. von Littrow. - Warsaw . . . . . Col. G. Du Plat (British Consul). - Washington . . . Lt. Maury, U.S. Navy. - Wilna . ### Institutions - Aberdeen . . . . . University. - Berlin . . . . . Academy of Sciences. - Bologna . . . . . Academy. - Bonn . . . . . University. - Boston . . . . . Academy of Sciences. - Bowdoin College . . . United States. - Bowditch Library . . . United States. - Cambridge . . . Trinity College. - Cherkow . . . . . University. - Dorpat . . . . . University. - Dublin . . . . . University. - Edinburgh . . . Observatory. - Edinburgh . . . Royal Society. - Edinburgh . . . University. - Glasgow . . . . . University. - Göttingen . . . University. - Harvard, U. S. . College. - Kiew . . . . . University. - Leyden . . . . . University. - House of Lords, Library . . . London. - House of Commons, Library . . . " , " - London . . . . . King's College. - London . . . . . Royal Institution. - Moscow . . . . . University. - Oxford . . . . . Savilian Library. - Paris . . . . . Academy of Sciences. - Paris . . . . . Board of Longitude. - Paris . . . . . Dépôt de la Marine. - Philadelphia . . . Philosophical Society. - Queen's Library . . . London. Royal Cornwall Polytechnic Society . . . . . Falmouth. St. Andrew's . . . . . University. St. Bernard . . . . . Convent. St. Petersburgh . . . . Academy of Sciences. St. Petersburgh . . . . Geographical Society. Stockholm . . . . . Academy of Sciences. Upsal . . . . . Society of Sciences. Waterville, U.S. . . . College Library. Individuals. Bache, Dr. A. D. . . . Washington. Birt, W. H., Esq. . . . London. Christie, S. H., Esq. . . Woolwich. Colebrooke, Sir W. . . Guiana. Demidoff, Prince Anatole de Florence. Dove, Prof. . . . Berlin. Erman, Dr. Adolph . . Berlin. Fox, R. W., Esq. . . Falmouth. Gauss, Prof. . . . Göttingen. Gilliss, Lt. J. M., U. S. Navy Washington. Harris, Sir W. Snow . . Plymouth. Holland, L., Esq. . . London. Howard, Luke, Esq. . . Tottenham. Humboldt, Baron . . . Berlin. Kaemtz, M. . . . Dorpat. Kupffer, A. T. . . . St. Petersburgh. Lawson, Henry G., Esq. . Bath. Lloyd, Rev. Dr. . . . Dublin. Loomis, Prof. . . . New York. Lowndes Prof. of Astronomy Cambridge. Lubbock, Sir John W., Bart. London. Lütke, Vice-Admiral . . St. Petersburgh. Mahlmann, Prof. . . . Berlin. Melvill, J. C., Esq. . . East India House. Mentchikoff, Prince . . St. Petersburgh. Phillips, John, Esq. . . York. Plumian Prof. of Astronomy Cambridge. President of the Royal Society London. Quetelet, A. . . . Brussels. Redfield, W. C., Esq. . . New York. Reid, Lieutenant-Colonel Barbadoes. Riddell, Capt., R.A. . . Woolwich. Roget, P. M., M.D. . . London. Sabine, Lieut.-Col., R.A. . Woolwich. Senftenberg, Baron von Prague. Smyth, W. H., Captain R.N. London. South, S'. James . . . " " Wartmann, Prof. Elie . . Lausanne. Wrangell, Vice-Admiral . . St. Petersburgh. Younghusband, Capt. . . Woolwich. ROYAL MEDALS. HER MAJESTY QUEEN VICTORIA, in restoring the Foundation of the Royal Medals, has been graciously pleased to approve the following regulations for the award of them: That the Royal Medals be given for such papers only as have been presented to the Royal Society, and inserted in their Transactions. That the triennial Cycle of subjects be the same as that hitherto in operation: viz. 1. Astronomy; Physiology, including the Natural History of Organized Beings. 2. Physics; Geology or Mineralogy. 3. Mathematics; Chemistry. That, in case no paper, coming within these stipulations, should be considered deserving of the Royal Medal, in any given year, the Council have the power of awarding such Medal to the author of any other paper on either of the several subjects forming the Cycle, that may have been presented to the Society and inserted in their Transactions; preference being given to the subjects of the year immediately preceding: the award being, in such case, subject to the approbation of Her Majesty. The Council propose to give one of the Royal Medals in the year 1848 for the most important unpublished paper in Astronomy, communicated to the Royal Society for insertion in their Transactions after the termination of the Session in June 1845, and prior to the termination of the Session in June 1848. The Council propose also to give one of the Royal Medals in the year 1848 for the most important unpublished paper in Physiology, including the Natural History of Organized Beings, communicated to the Royal Society for insertion in their Transactions after the termination of the Session in June 1845, and prior to the termination of the Session in June 1848. MDCCCXLVIII. The Council propose to give one of the Royal Medals in the year 1849 for the most important paper in Physics, communicated to the Royal Society after the termination of the Session in June 1845, and prior to the termination of the Session in June 1848, and printed in the Philosophical Transactions. The Council propose also to give one of the Royal Medals in the year 1849 for the most important paper in Geology or Mineralogy, communicated to the Royal Society after the termination of the Session in June 1845, and prior to the termination of the Session in June 1848, and printed in the Philosophical Transactions. The Council propose to give one of the Royal Medals in the year 1850 for the most important paper in Mathematics, communicated to the Royal Society after the termination of the Session in June 1846, and prior to the termination of the Session in June 1849, and printed in the Philosophical Transactions. The Council propose also to give one of the Royal Medals in the year 1850 for the most important paper in Chemistry, communicated to the Royal Society after the termination of the Session in June 1846, and prior to the termination of the Session in June 1849, and printed in the Philosophical Transactions. The Council propose to give one of the Royal Medals in the year 1851 for the most important paper in Astronomy, communicated to the Royal Society after the termination of the Session in June 1847, and prior to the termination of the Session in June 1850, and printed in the Philosophical Transactions. The Council propose also to give one of the Royal Medals in the year 1851 for the most important paper in Physiology, including the Natural History of Organized Beings, communicated to the Royal Society after the termination of the Session in June 1847, and prior to the termination of the Session in June 1850, and printed in the Philosophical Transactions. CONTENTS. I. The Bakerian Lecture.—Researches on the Tides. Thirteenth Series. On the Tides of the Pacific, and on the Diurnal Inequality. By the Rev. W. Whewell, D.D., F.R.S. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 1 II. On the Solution of Linear Differential Equations. By Charles James Hargreave, Esq., B.L., F.R.S., Professor of Jurisprudence in University College, London . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 III. On a new substance occurring in the Urine of a patient with Mollities Ossium. By Henry Bence Jones, M.A., F.R.S., Physician to St. George’s Hospital 55 IV. Examination of the proximate Principles of some of the Lichens. By John Stenhouse, Esq., Ph.D., Glasgow. Communicated by Thomas Graham, Esq., F.R.S. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 V. On the Heat disengaged during Metallic Substitutions. By Thomas Andrews, M.D., M.R.I.A., Vice-President of Queen’s College, Belfast, &c. Communicated by Michael Faraday, Esq., F.R.S. &c. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 VI. Report of Observations made upon the Tides in the Irish Sea, and upon the great similarity of Tidal Phenomena of the Irish and English Channels, and the importance of extending the Experiments round the Land’s End and up the English Channel. Embodied in a letter to the Hydrographer. By Captain F. W. Beechey, R.N., F.R.S. Communicated by G. B. Airy, Esq., F.R.S. &c., Astronomer Royal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 VII. On the Blow-hole of the Porpoise. By Francis Sibson, Esq. Communicated by Thomas Bell, Esq., F.R.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 VIII. On the Corrections to be applied to the Monthly Means of Meteorological Observations taken at any hour, to convert them into Mean Monthly values. By James Glaisher, Esq., of the Royal Observatory at Greenwich. Communicated by G. B. Airy, Esq., F.R.S. &c., Astronomer Royal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 IX. On the Structure of Chitons. By J. E. Gray, Esq., F.R.S., F.Z.S. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 X. An Investigation on the Chemical Nature of Wax.—I. On Cerotic Acid, a new Acid contained in Bees’-Wax. By Benjamin Collins Brodie, Esq. Communicated by Sir Benjamin C. Brodie, Bart., F.R.S. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 XI. An Investigation on the Chemical Nature of Wax.—II. On the Chemical Nature of a Wax from China. By Benjamin Collins Brodie, Esq. Communicated by Sir Benjamin C. Brodie, Bart., F.R.S. &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 ADJUDICATION of the Medals of the Royal Society for the year 1848 by the President and Council. The Copley Medal to John Couch Adams, Esq., for his "Investigations relative to the disturbances of Uranus, and for his application of the inverse problem of perturbations thereto." The Royal Medal in the department of Astronomy, to Thomas Galloway, Esq., for his Paper "On the Proper Motion of the Solar System," published in the Philosophical Transactions for 1847. No recommendation of the Royal Medal in the department of Physiology having been received, this Medal was awarded to Charles James Hargreave, Esq., for his Paper entitled "On the Solution of Linear Differential Equations," published in the Philosophical Transactions for 1848. The Rumford Medal to M. V. Regnault, for his "Experiments to determine the Laws and the numerical data which enter into the calculation of Steam-Engines." The Bakerian Lecture for 1848 was delivered by The Rev. William Whewell, D.D., F.R.S., and entitled "On the Tides of the Pacific, and on the Diurnal Inequality." CONTENTS. XII. Observations on some Belemnites and other Fossil Remains of Cephalopoda, discovered by Mr. Reginald Neville Mantell, C.E. in the Oxford Clay near Trowbridge, in Wiltshire. By Gideon Algernon Mantell, Esq., LL.D., F.R.S., F.L.S., Vice-President of the Geological Society . . . . . . . page 171 XIII. On the Structure of the Jaws and Teeth of the Iguanodon. By Gideon Algernon Mantell, Esq., LL.D., F.R.S., F.L.S., Vice-President of the Geological Society, &c. . . . . . . . . . . . . . . . . . . . . . . . 183 XIV. Determinations of the Magnetic Inclination and Force in the British Provinces of Nova Scotia and New Brunswick, in the Summer of 1847. By Professor George W. Keely, of Waterville College, Maine, United States. Communicated by Lieut.-Colonel Sabine, For. Sec. R.S. . . . . . . . . . . . . . . . . . . . . . . . . 203 XV. On a new Case of the Interference of Light. By the Rev. Baden Powell, M.A., F.R.S., F.R.A.S., F.G.S., Savilian Professor of Geometry in the University of Oxford . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 XVI. On the Theory of certain Bands seen in the Spectrum. By G. G. Stokes, M.A., Fellow of Pembroke College, Cambridge. Communicated by the Rev. Baden Powell, M.A., F.R.S., &c. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 XVII. An Experimental Inquiry undertaken with a view of ascertaining whether any, and what signs of current Electricity are manifested during the organic process of Secretion in living animals, being an attempt to apply some of the discoveries of Faraday to Physiology. By H. F. Baxter, Esq. Communicated by Sir Benjamin Brodie, Bart., F.R.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243 XVIII. On the Direction assumed by Plants. By Professor Macaire of Geneva. Communicated by P. M. Roget, M.D., Sec. R.S. . . . . . . . . . . . . . . . . . . . . . . . . . 253 XIX. Microscopical Examination of the Contents of the Hepatic Ducts, with conclusions founded thereon as to the Physiological signification of the Cells of Hepatic Parenchyma, and as to their Anatomical relation to the Radicles of the Hepatic Ducts. By T. Wharton Jones, F.R.S. . . . . . . . . . . . . . . . . . . . . . . . . . 277 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 APPENDIX. Presents