VI CONTENTS. 



Page 



On the Moulting Process in the Cray Fish 331 



Route from Lima by the Quebrada of San Mateo, by J. Maclean, 



Esq. of Lima 333 



Action of ^ther on Indigo, by M. Vogel 334 



Effects of Mushrooms on the Air 334 



Stars at present undiscoverable in the Heavens 335 



Meteorological Observations for August, 1839 335 



. Table 336 



NUMBER XCVIL— NOVEMBER. 



Prof. De Morgan on the Rule for finding the Value of an An- 

 nuity on three Lives 337 



Dr. J. Draper on the Use of a Secondary Wire as a Measure of 



the Relative Tension of Electric Currents 339 



On the Application of Electro-magnetism as a Motive Power : 

 in a Letter from Professor P. Forbes of Aberdeen, to Michael 



Faraday, D.C.L., &c 350 



Mr. Lubbock on the Wave-surface in the Theory of Double 



Refraction 35 1 



Prof. Faraday's Experimental Researches in Electricity. — Fif- 

 teenth Series ^ 358 



Mr. E. Cooper's Observations of Shooting Stars made on the 



Night of August 10, 1839 372 



Col. R. Wright's Meteorological Observations during a Resi- 

 dence in Colombia between the Years 1820 and 1830 374 



Prof. J. D. Forbes's Letter to the Editor of the Scientific Me- 

 moirs respecting a Paper on the Polarization of Heat, in the 



Sixth Number of that Journal , 380 



Mr. J. T. Towson on the proper Focus for the Daguerreotype 381 

 Mr. Ivory (The Bakerian Lecture) on the Theory of the Astro- 

 nomical Refractions 385 



Proceedings of the Geological Society 396 



On the Presence of Iodine in Coal Formations, by M. Bussy. . 411 



Preparation of Chlorosalts, by M. Filhol 411 



Chloro-Stannite of Mercury, by M. Capitaine 413 



Anhydrous Protochloride of Tin, by M. Capitaine 414 



Meteorological Observations for September 415 



Table 416 



NUMBER XCVIII. -DECEMBER. 



Dr. C. Schafhaeutl on the Combinations of Carbon with Silicon 

 and Iron and other Metals, forming the different species of 

 Cast Iron, Steel, and malleable Iron 417 



