viii CONTKNTS OF VOL. XXX. nilRI) SERIES. 



Page 

 Professors Wohlcr and Liebig on Thialdine and Selcnaldine, 



two new artificial organic bases "I'O 



Dr. K. A. Smitli's Remarks on the Air and Water of Towns. . 478 

 Mr. W. U. Birt on certain Atmospheric or Barometric Waves 



whicii traversed Europe during Novemljer 1842 482 



Sir G. C. Haughton's Experiments proving the common nature 



of Magnetism, Cohesion, Adhesion and Viscosity {concluded) 502 



On Carotin 523 



On the Preparation of Iodide of Lead 524 



On the Action of Bromine upon certain Salts, by M. Augusta 



Cahours • • • 525 



A Chemiciil Investigation of some Silicates containing Chlorine, 



Sulphuric and Carbonic Acid, by M. Whitney of Boston, 



United States. . ._ 528 



Meteorological Observations for April 1847 529 



Table 530 



Inde.K 531 



PLATES. 



1. Illustrative of Dr. Waller's Paper on Hail, and on the Organic Bodies 



contained in Hailstones, &c. 

 II. Illuslrative of the Rev. H. Moseley's Paper on a Machine for calcula- 

 ting the Products, Quotients, Logarithms, and Powers of Numbers. 



III. Illustrative of Mr. Hopkins's Paper on the Hourly Alterations of the 



Vapour Atmosphere at Bombay. 



IV. Ilkistrative of Prof. Wartmann's Paper on Induction. 



V. Illustrative of Dr. Waller's Paper on the Microscopic B^xamination 

 of the Papillae and Nerves of the Tongue of the Frog. 



VI. Illustrative of Sir D. Brewster's Paper on the Knowledge of Distance 

 given by Binocular Vision. 



VII. Illustrative of -Mr. Cooke's Paper on the Use of a double Circuit in 

 the measurement of Electrical Forces. 



