CONTKNTS. V 



Page 



Seleniuret of Lead 233 



Selenium in the Sulphur of the Lipari Isles 234 



Latrobite 235 



On the Teeth of the Koala , 235 



On the Umbilicus of Marsupial Animals 235 



Method of fixing Crayon Colours 236 



New Scientific Books 237 



New Patents , 237 



Mr. Howard's Meteorological Journal 239 



NUMBER IV.— OCTOBER. 

 Mr. Gray on the Synonima of the Genera Anomia, Crania Orbicula, and 



Discina 241 



Mr. South's Corrections in Right Ascension of 37 Principal Stars 245 



M. Andre del Rio's Analysis of an Alloy of Gold and Rhodium from the 



Parting House, at Mexico. 251 



Col. Beaufoy's Astronomical Observations 256 



Mr. Wallan on the Seat of Vision 258 



M. Ferre's Summary View of the Application of the Electro-chemical 



Theory to Chemical Phaenomena 262 



Dr. Moll on the Velocity of Sound 268 



On Copper Sheathing , , 281 



M- Rose's Analysis of the Seleniurets of the Eastern Harz 284 



A Table of Chemical Equivalents .... 293 



Mr. Phillips's Reply to Dr. Christison ......,,.,., 298 



Mr. Herries on an improved Air-pump. (With a Plate.) 301 



Mr. Dalton on the Analysis of Atmospheric Air by Hydrogen 304 



Analytical Account of the Journal of the Academy of Natural Sciences of 



Philadelphia, Vol. iv. Part 2. . . .^. ....... . 306 



Petrifactions of Mount Carmel. ,. 312 



On the flexible or elastic JNIarble of Berkskire County 313 



Extraordinary Minerals discovered in Warwick, New York 314 



Lepidolite 315 



Helvin 315 



On Lamouroux's New Division of the Animal Kingdom 315 



On theJBLorn of Plenty, a Variety of the Common Garden Snail 316 



New Scientific Books , , . 3 1 7 



New Patents 318 



Mr. Howard's Meteorological Journal , ■. 3 19 



NUMBER V— NOVEMBER. 



Mr. Major on a Digest of the Pians of Ships in the British Navy . ...... 321 



Col. Beaufoy's Astronomical Observations ,...„,...,. 329 



Mr. Brooke's Reply to Dr. BreA'ster ,,,.,.,... . . 330 



