39P 



CONTENTS OF VOL. XXVII 



(FOURTH SERIES.) 



NUMBER CLXXIX.— JANUARY 1864. 



Page 

 Prof. Le Conte on the Adequacy of Laplace's explanation to 

 account for the Discrepancy between the Computed and the 



Observed Velocity of Sound in Air and Gases 1 



Sir David Brewster on the Stereoscopic Relief in the Chimenti 



Pictures 33 



Mr. G. F. Rodwell on some Effects produced by a Fluid in 



Motion 36 



Prof. Tyndall on Laplace's Correction for the Velocity of Sound. 41 

 Mr. A. Cayley on an Analytical Theorem relating to the four 

 Conies inscribed in the same Conic and passing through the 



same three Points 42 



Mr. A. Cayley on an Analytical Theorem relating to the Sec- 

 tions of a Quadric Surface 43 



M. A. Wullner on the Absorption of Light 44 



Mr. S. M. Drach on deducing the Parallax of Mars, and thence 

 that of the Sun, from the former's Geocentric Velocity when 



in opposition, and especially near the Node 50 



Mr. J. Napier on the Dynamics of the Galvanic Battery .... 52 

 Mr. T. A. Malone on the Gas Battery of Mr. Grove ; and its 



Theory 54 



M. A. Colding on the History of the Principle of the Conserva- 

 tion of Energy 56 



Notices respecting New Books : — 



The Rev. R. Main's Practical and Spherical Astronomy, 



for the use chiefly of Students in the Universities .... 64 

 Mr. W. T. Lynn's First Principles of Natural Philosophy. 66 

 Mr. J. Wharton's Complete Solutions of every class of 

 Examples in Algebra, forming a complete Course on the 

 subject, and calculated to facilitate and extend the Study 



of Mathematics as a logical Course 67 



Proceedings of the Royal Society : — 



Mr. A. J. Ellis on a Simple Formula and Practical Rule 

 for calculating Heights barometrically without Loga- 

 rithms 68 



Proceedings of the Geological Society : — 



Herr A. von Koenen on the Correlation of the Oligocene 

 Deposits of Belgium, Northern Germany, and the South 

 of England 73 



