IV CONTF.NTS. 



Pngp 



Meteorological Observations made at the Apartments of the 

 rJoyal Society by the Assistant Secretary; by Mr. Thomp- 

 son at the Garden of the Horticultural Society at ChisM'ick, 

 near London; and bv Mr. Veall at Boston 80 



NUMBER LII.— AUGUST. 



Kev. W. Ritchie on the Cause of the remarkable Difference 

 between the Attractions of a Permanent and of an Electro- 

 magnet on Soft Iron at a Distance SI 



Remarks on the Rev. J. H. Pratt's Demonstration of a Propo- 

 sition in the Mecauiqiie Celeste S't 



Mr. J. D. Smith on the Hydrates of Barytes and Strontia .... 87 

 Mr. J. G. Children's Notice respecting Dr. Ehrenberg's Collec- 

 tions of dried Iiifusoria, and other microscopic Objects. ... 90 

 Prof. J. R. Young's concluding Remarks on the Theory of 



Vanishing Fractions 92 



Mr. J. Nixon's Heiijhts of Whernside, Great Whernside, Rum- 

 ble's Moor, Pendle Hill, and Boulsworth 96 



Mr. J.W. Lubbock on a Property of the Parabola 100 



Mr. E. Rudge on the Position of the South Magnetic Pole , . 104- 



Mr. G. J. Knox and the Rev. T. Knox on Fluorine 107 



Mr. G. Bird on certain new Combinations of Albumen, with an 

 Account of some curious Properiies peculiar to that Sub- 

 stance 109 



Rev. Baden Powell's Remarks on the Formula for the Disper- 

 sion of Light (concluded- ) 116 



Mr. F. W. Mullins on certain Improvements in the Construc- 

 tion of Magneto-electrical Machines, and on the Use of 



Caoutchouc for Insulation in Voltaic Batteries 120 



Letter from Mr. Faraday to Mr. Brayley on some former Re- 

 searches relative to the peculiar Voltaic Condition of Iron re- 

 observed by Professor Schoenbein, supplementary to a Letter 



to .Mr. Phillips, in the lust Number 122 



Mr. T. Weaver on the Carboniferous Series of the United States 



of North America 124 



Mr. W. Sturgeon on Electro- pulsations and Electro-momentum 132 

 New Books: — Chev. F. M. G. De Pambour's Practical Treatise 



on Locomotive Engines upon Railwaj's 135 



Proceedings of the Zoological Society 136 



Effects of compressed Air on the Human Body 147 



Gastric Juice 14S 



Bibromide of Mercury ] 48 



Fluorine 1 49 



Antimonial Copper (E'clatant ) 149 



On the Action of Bromine upon .Sther 149 



On the Composition of the crystallized Hydrate of Potash . . 151 

 On the Combinations ofChromium with Fluorine and Chlorine 151 



