CONTENTS. XI 



ARTICLE XL 



Improved Process for obtaining Potassium. By Robert Hare, M.D., Professor of 



Chemistry in the University of Pennsylvania. ..... 341 



ARTICLE XII. 



Engraving and Description of a Rotatory Multiplier, or one in which one or more 

 Needles are made to revolve by a Galvanic Current. By R. Hare, M. D., Profes- 

 sor of Chemistry in the University of Pennsylvania. .... 343 



ARTICLE XIIL 



Contributions to the Geology of the Tertiary Formations of Virginia. — Second Series. 

 By William B. Rogers, Professor of Natural Philosophy in the University of Vir- 

 ginia, and Henry D. Rogers, Professor of Geology and Mineralogy in the Univer- 

 sity of Pennsylvania. ........ 347 



ARTICLE XIV. 



Contributions to the Geology of the Tertiary Formations of Virginia. — Second Series — 

 Continued : Being a Description of several Species of Meiocene and Eocene Shells, 

 not before described. By William B. Rogers, Professor of Natural Philosophy in 

 the University of Virginia, and Henry D. Rogers, Professor of Geology and Mine- 

 ralogy in the University of Pennsylvania. ...... 371 



ARTICLE XV. 



Report of the Committee on the Solar Eclipse of May 14 and 15, 1836. - - 379 



ARTICLE XVI. 



'^Abstract of Meteorological Tables in the possession of the American Philosophical 



Society. -.-----.-- 395 



Donations to the Library and Cabinet. ...... 399 



