CONTENTS OF VOL. XXI. Vll 



Page 

 Mr. Murchison on the Salt Steppe south of Orenburg, and 



on a remarkable Freezing Cavern 357 



Extracts from a Letter addressed by Sir J. F. W. Herschel to 

 Mr. Murchison, explanatory of the Phenomena of the Freezing 



Cave of Illetzkaya Zatchita 359 



Sir J. F. W. Herschel on some Phenomena observed on Glaciers, 

 and on the internal Temperature of large Masses of Ice or 

 Snow, with some Remarks on the natural Ice -caves which 



occur below the limit of perpetual Snow 362 



Proceedings of the Geological Society 365 



Chemical Society 378 



Royal Irish Academy 389 



— Royal Astronomical Society 397 



Institution of Civil Engineers 401 



London Electrical Society 404 



New Books : — Newman on the Difficulties of Elementary Geo- 

 metry, &c. — Logarithmic and Trigonometric Tables, &c. . . 405 



Prof. MacCullagh on the Law of Double Refraction 407 



Atomic Weight of Elements 409 



On a very curious Fact connected with Photography, disco- 

 vered by M. Moeser of Koenigsberg, communicated by Prof. 



Bessel to Sir D. Brewster. 409 



Use of Iron Wire for Secondary Electro-magnetic Coils 411 



Non-conversion of Calomel into Sublimate by the Alkaline 



Chlorides 411 



Method of distinguishing Zinc from Manganese in Solutions 



containing Ammoniacal Salts, by M. Otto 412 



On MM. Varrentrapp and Will's Method of determining Azote 



in Organic Analyses, by M. Reizet 412 



New Double Salt of Soda and Protoxide of Platina 413 



Composition of Conia 414 



Mr. Luke Howard's Cycle of Eighteen Years in the Seasons 



of Britain 415 



Meteorological Observations for September 1842 415 



Table 416 



NUMBER CXL.— DECEMBER. 



Prof. Grove on a Gaseous Voltaic Battery 417 



Prof. Daniell on the Constant Voltaic Battery 421 



The Rev. P. Kelland on certain Arguments adduced in the last 



Number of the Philosophical Magazine 422 



The Rev. Prof. Challis on the Analytical Condition of Rectilinear 



Fluid Motion, in Reply to Mr. Stokes's Remarks 423 



Dr. A. Waller's Experiments on the coloured Films formed by 



Iodine, Bromine, and Chlorine upon various Metals 426 



Mr. Earnshaw's Reply to Professor Kelland's Defence of the 



Newtonian Law of Molecular Action 437 



The Rev. J. Booth on a Theorem in Analytical Geometry .... 444 



