CONTENTS. Vll 



Page 

 gation and Nautical Astronomy; and Davies's Researches 



in Spherical Geometry 363 



Proceedings of the Geological Society 368 



Zoological Society 372 



Royal Society of Edinburgh 379 



M. Pelletier's Analyses of Vegetable Substances {continued). . 381 



On Ambreine, Ambreic Acid, and Cholesteric Acid , 382 



M. Lassaigne on the Iodides of Platina and their Compounds 384 



Peroxide of Bismuth t 387 



Separation of Bismuth and Lead — Composition of Oil of Bitter 



Almonds 389 



Mr. W. Sturgeon on the Thermo-Magnetism of Single Pieces 

 of Metal, and on the Electro-Decomposition of Metallic 



Solutions 392 



Return of the Expedition under Captain Ross 394 



Corrections in Mr. Prideaux's Paper on the Voltaic Theory . . 398 

 Occultations of Fixed Stars by the Moon, in November 1833 399 

 Meteorological Observations 400 



NUMBER XVIII.— DECEMBER. 



Sir John F. W. Herschel on the Absorption of Light by Co- 

 loured Media, viewed in connexion with the Undulatory 



Theory 401 



Rev. B. Powell's Remarks on Mr. Barton's Reply respecting 



the Inflection of Light 412 



Mr. J.Henry on Mr. Murphy's Proof of the Existence of a real 



or imaginary Root for any proposed Equation 417 



Mr. W. J. Henwood's Observations on the Rise and Fall of 

 Water in some Wells in Cornwall, with brief Notices of other 

 Matters bearing on the Phenomena of Springs ; in a Letter 



to Sir Charles Lemon, Bart. M.P. F.R.S 417 



Mr. R. Potter, Jun., on a brilliant Arch of an Aurora Borealis 



seen on the Evening of March 21, 1833 422 



Mr. A. Walker on the Cause of the Direction of Continents 

 and Islands, Peninsulas, Mountain Chains, Strata, Currents, 



Winds, Migrations and Civilization 426 



Rev. H. Moseley on the Theory of Resistances in Statics 431 



Mr. J. Blackwall's Characters of some undescribed Genera and 



Species of Araneidce 436 



Mr. R.Phillips's Observations on the Use of Chemical Symbols 443 



Proceedings of the Royal Society 446 



Philosophical Society of Cambridge 461 



New Books : — Berzelius's Analysis of Inorganic Bodies 463 



The Sciagraphicon 464 



