﻿CONTENTS 'of N° 250.— Fourth Series. 



XLIV. Researches in British Mineralogy. By David Forbes, 



F.R.S. &c ...page 321 



XLV. Lecture Experiments to illustrate the Laws of Motion. By 



Professor Robert Ball, A.M 332 



XLVI. On Shadow Optometers. By John C. Douglas, East- 

 India Government Telegraph Department 34 ° 



XLVII. On the Cause of a Pink Colour in White-Lead Corrosions. 

 By William Baker, F.C.S., Associate of the Royal School of Mines, 



London 344 



XLVIII. On the Colour of the Lake of Geneva. By L. Soret. . 345 

 XLIX. Fundamental Principles of Molecular Physics. By Pro- 

 fessor J. Bayma, S. J., of Stonyhurst College 348 



L. On some Reactions of Hydrated Oxide of Ethylene- sodium. 

 By J. Alfred Wanklyn, Professor of Chemistry in the London In- 

 stitution 358 



LI. On the Mechanical Impossibility of the Descent of Glaciers by 

 their Weight only. By Henry Moseley, M.A., Canon of Bristol, 



F.R.S., Instit. Imp. Sc. Paris, Corresp 363 



LII. On the Uniform Motion of an Imperfect Fluid. By Henry 



Moseley, F.R.S. &c 37 ° 



LIII. Note on a new Continued Fraction applicable to the Quadra- 

 ture of the Circle. By J. J. Sylvester 373 



LIV. On two remarkable Resultants arising out of the Theory of 

 Rectifiable Compound Logarithmic Waves. By J. J. Sylvester . . 375 



LV. Notices respecting New Books : — Physical and Historical 

 Evidences of vast Sinkings of Land on the North and West Coasts of 

 France, and South-western Coasts of England, within the Historical 

 Period. Collected and commented on by R. A. Peacock, Esq., C.E. 



On Steam as the Motive Power in Earthquakes and Volcanoes, and 



on Cavities in the Earth's Crust. By R. A. Peacock, Esq., C.E. 382-384 

 LVI. Proceedings of Learned Societies : — 



Royal Society:— Prof. Tyndall on the Blue Colour of the Sky, 

 the Polarization of Skylight, and on the Polarization of Light 



by Cloudy matter generally 384 



Royal Institution : — Dr. A. Crum Brown on Chemical Con- 

 stitution, and its Relation to Physical and Physiological Pro- 

 perties 395 



LVII. Intelligence and Miscellaneous Articles: — 



On a Mirage in the English Channel, by John Parnell, M.A., 



F.R.A.S 400 



On the production of a beautiful Patina on Bronzes in large Towns. 401 

 On Tyndall's Cometary Theory, by Mr. E. Carpmael and W. B. 

 Gibbs, F.R.A.S. 403 



%* It is requested that all Communications for this Work may be addressed, 

 post-paid, to the Care of Messrs. Taylor and Francis, Printing Office, Eed 

 Lion Court, Fleet Street, London^ 



