CONTENTS. V 



Page 



Prof. Encke on Olbers's Method of determining the Orbits of 



Comets (continued) 203 



Proceedings of the Royal Society 207 



Geological Society 212 



. Zoological Society 222 



Mr. Sturgeon's Explanatory Facts 231 



N. S. Heineken on a Method of ascertaining, approximately, 



the Radii of Curvature of unequally convex Lenses 23* 



Arsenic in English Sulphuric Acid 235 



Appearance of Halley's Comet 236 



Congres Scietttifique at Douay 237 



Dublin Meeting of the British Association for the Advance- 

 ment of Science 237 



Succinic Acid and its Combinations 238 



New Locality of Plenakite 239 



Meteorological Observations 240 



NUMBER XL.— OCTOBER. 



Mr. C. Rumker on a new Method of reducing Lunar Observa- 

 tions for the Determination of the Longitude 241 



Sir David Brewster's Observations relative to the Structure 



and Origin of the Diamond 245 



Mr. Carter on the Ancient and Modern Formation of Deltas 

 in the Persian Gulf by the Euphrates and Tigris, in answer 



to Mr. Beke 250 



Dr. H. Hudson's Proposed Method for inferring the Dew- 

 point from the Indications of the Wet-bulb Hygrometer . . 256 

 Dr. Apjohn's Experimental Investigation of a Formula for 

 inferring the Dew-point from the Indications of the Wet- 

 bulb Hygrometer 266 



Mr. C. B. Rose's Sketch of the Geology of West Norfolk 



(continued) - 274 



Prof. Encke on Olbers's Method of determining the Orbits of 



Comets (concluded) 280 



Official Report of the Proceedings of the British Association 

 for the Advancement of Science, at the Dublin Meeting, 



August 1835 ; Mathematics and Physics 289 



Proceedings of the Geological Society 316 



. Zoological Society 328 



On the Existence of Arsenic in Phosphorus 331 



Mr. J. F. W. Johnston's Composition of Oxychloride of Anti- 

 mony 332 



Collection of Minerals and North American Fossils 334 



Letter from Mr. Watkins 335 



Analysis of Wolfram 335 



Meteorological Observations 336 



