XII. Remarks on Affinity. By M. DUMAS ... page By XIII. On the Heating of a Disk by rapid rotation in vacuo. Messrs. B. STEWART and P. G. TAIT.. XIV. Fundamental Principles of Molecular Physics. By Professor W. A. NORTON .... XV. On the Temperature of Flames, and its relations with the Pressure. By M. H. ST.-CLAIre Deville XVI. On Ethylate of Sodium and Ethylate of Potassium.-Part. I. By J. ALFRED WANKLYN, Professor of Chemistry in the London Institution XVII. On the Relation of Hydrogen to Palladium. By THOMAS GRAHAM, F.R.S., Master of the Mint ...... XVIII. On some Phenomena of Binocular Vision. By JOSEPH XIX. Notices respecting New Books:-Mr. J. N. LOCKYER'S 1 11 12 131 141 XX. Proceedings of Learned Societies: ROYAL SOCIETY:-Lieut. J. HERSCHEL on the Lightning Spectrum; Mr. J. N. LOCKYER on the Spectrum of a Solar Prominence; and Spectroscopic Observations of the Sun .. 141-145 GEOLOGICAL SOCIETY :-Dr. J. SCHMIDT on the Eruption of the Kaimeni of Santorin; Mr. J. PRESTWICH on the Structure of the Crag-beds of Norfolk and Suffolk; Mr. J. THOMSON on some genera of Carboniferous Corals; Mr. S. V. WOOD, Jun., on the Pebble-beds of Middlesex, Essex, and Herts; Mr. W. TOPLEY on the Cretaceous Rocks of the Bas-Boulonnais; Mr. R. B. FOOTE on the Distribution of Stone Implements in Southern India; Sir PHILIP DE M. GREY EGERTON on some new fossil Fish from the Lias of Lyme Regis; Mr. J. W. SALTER on a true Coal-plant from Sinai, and on some Fossils from the Menevian Group; Mr. W. B. DAWKINS on a new Species of Fossil Deer from Clacton and the Norwich Crag; Mr. E. R. LANKESTER on the remains of Pteraspidian Fishes in Devonshire and Cornwall 145-156 XXI. Intelligence and Miscellaneous Articles : On the Temperature of Flames and Dissociation, by E. Vicaire. 156 **It is requested that all Communications for this Work may be addressed, post-paid, to the Care of Messrs. Taylor and Francis, Printing Office, Red Lion Court, Fleet Street, London. Mar. 18 Published the First Day of every Month.-Price 2s. 6d. THE LONDON, EDINBURGH, AND DUBLIN PHILOSOPHICAL MAGAZINE, AND JOURNAL OF SCIENCE. Being a Continuation of Tilloch's Philosophical Magazine,' Nicholson's Journal,' and Thomson's Annals of Philosophy?' CONDUCTED BY SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. AND WILLIAM FRANCIS, PH.D. F.L.S. F.R.A.S. F.C.S. FOURTH SERIES. N° 248.-MARCH 1869. LONDON: PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, Printers and Publishers to the University of London. Sold by Longmans, Green, Reader and Dyer; Kent and Co.; Simpkin, Marshall and Co.; Whittaker and Co.; and H. Baillière, London :—and by A. and C. Black, and Thomas Clark, Edinburgh; Smith and Son, Glasgow:-Hodges and Smith, Dublin:-and Putnam, New York. Now ready, in post 8vo, with 86 Diagrams, price 7s. 6d. THE THEORY OF OCULAR DEFECTS AND OF SPECTACLES. Translated from the German of Dr. HERMANN SCHEFFLER by ROBERT BRUDENELL CARTER, F.R.C.S. (Exam.), Fellow of the Royal Medical and Chirurgical Society, Consulting Surgeon to the Gloucestershire Eye Institution. With Prefatory Notes and a Chapter of Practical Instructions. London: Longmans, Green, and Co., Paternoster Row. UNIVERSITY OF LONDON. Just published, Price 4s. THE CALENDAR FOR THE YEAR 1869; Containing the Regulations for each Examination, the Examination Papers set during the past year, and other information. Price 2s. 6d. THE GENERAL REGISTER OF GRADUATES AND to February 1st, 1869. Taylor and Francis, Printers and Publishers to the University, 392 pp. 8vo, 15s., THE MECHANICAL THEORY OF HEAT, With its APPLICATIONS to the STEAM-ENGINE and to the PHYSICAL PROPERTIES OF BODIES. By R. CLAUSIUS, Professor of Physics in the University of Zurich. Professor of Mathematics in University College, London. First English Edition. Post 8vo, cloth, 10s. 6d. A MANUAL OF INORGANIC CHEMISTRY. Arranged to facilitate the Experimental Demonstration of the Facts and Principles of the Science. By CHARLES W. ELIOT, Professor of Analytical Chemistry and Metallurgy in the Massachusetts Institute Professor of General and Industrial Chemistry in the Massachusetts Post 8vo, price 10s. 6d. AN INTRODUCTION TO PHARMACEUTICAL CHEMISTRY. By JOHN ATTFIELD, Ph.D., F.C.S., Professor of Practical Chemistry to the Pharmaceutical Society of Great Britain. John Van Voorst, 1 Paternoster Row. ADVERTISEMENTS continued on 3rd page of Cover. THE LONDON, EDINBURGH, AND DUBLIN PHILOSOPHICAL MAGAZINE AND JOURNAL OF [FOURTH SERIES.] MARCH 1869. XXII. Historical Notes on some Phenomena connected with the Boiling of Liquids. By CHARLES TOMLINSON, F.R.S.* 1. WE WHEN water is heated to that temperature at which its tension equals the whole pressure of both air and vapour on its surface, and it begins to emit steam not only from its surface (as it did before), but from all parts of its depth, it is said to be boiling. The boiling-point of any liquid means, therefore, the temperature at which its evaporating tendency equals the pressure of the atmosphere at the time-or the lowest temperature at which its vapour can have the elasticity of common air. 2. During many years after the invention of the barometer, and the consequent discovery of atmospheric pressure, it was supposed that the above statements contained a sufficient account of boiling. It was not until the irregular shifting of the boiling-point in thermometers under a constant pressure had been insisted on by such men as De Luc, Shuckburg, Horsley, and Cavendish, that steps were taken to determine the conditions on which that instrument should be constructed. The Royal Communicated by the Author. [In preparing the paper "On Boiling Liquids" recently read before the Royal Society, I was led to consult a good many books and memoirs, and to accumulate a number of historical details which, though not adapted to the Proceedings' of a Society whose chief object is to assist the progress of living science, may yet, if briefly stated, be acceptable in the Philosophical Magazine, which performs the useful functions both of critic and of observer. The insertion of these historical details may serve to correct some errors that have crept into our text-books.] Phil. Mag. S. 4. Vol. 37. No. 248. Mar. 1869. M Society gave the sanction of its high authority to a Report on the subject prepared by some of its most distinguished members, and published in the Transactions for the year 1777. In this Report the want of fixity in the boiling-point of water under a constant pressure is noticed, and the cause is referred to the depth of water in the vessel, which causes it to boil in gusts. It was found, however, that the elasticity of the steam from boiling water fairly represents the atmospheric pressure, and it was recommended that the water be boiled in a metal vessel constructed so as to allow the bulb, and nearly the whole of that part of the stem that contained mercury, to be surrounded by the steam. 3. I am not aware that in this Report, or in the results previously published that led to it, it is anywhere stated that the nature of the vessel influences the boiling-point. That fact was distinctly brought forward by M. Achard in 1785*. Distilled water was boiled in a brass cylindrical vessel by means of a spiritlamp, the thermometer-bulb being within half an inch of the bottom. Under these conditions the temperature was constantly varying, although the water appeared to boil equably. Blowing on the side of the vessel, opening and shutting a door, or anything that produced an agitation in the air caused a fall in the thermometer of 1·12° R. When the water was boiled in a matrass of white glass, there was no variation in the boiling-point as indicated by the thermometer. Achard performed a large number of experiments on the boiling-point of water in vessels of silver, brass, porcelain, earthenware, glass, &c., many of them being articles in domestic use; and he gives drawings of them in three folding plates, with measurements of their dimensions, to justify his conclusion (afterwards found to be erroneous) that in vessels of the same material the temperature of boiling water varies according to the size of the opening. There is no doubt, however, as to the influence of the vessel on the boiling-point. He says: "Le degré de chaleur de l'eau en ébullition dans différens vases est différent pour la même pression atmosphérique quoiqué les vases soient chauffés de la même manière et qu'ils se trouvent dans le même bain de sable." His idea was, that, metal being a good conductor, the heat readily escaped from it when the air was agitated, while glass retained its heat, and hence the oscillation of the mercury in the one case and its fixity in the other. He concludes his memoir with the remark "that the experiments. prove that the degree of heat of boiling water under an equal 66 * Nouveaux Mémoires de l'Académie Royale de Berlin for 1785, published in 1787. The following is the title of the memoir :- Expériences faites dans la vue de s'assurer si le degré de chaleur de l'eau pure bouillante est un degré fixe et invariable, indépendant de toute autre circonstance que de la pression de l'atmosphère." |
