CONTENTS. 



PAGE 



Art. I. On the Nucleus of the Animal and Vegetable " Cell.'* 

 By Martin Barry, M.D., F.R.S., London and 

 Edinburgh, Member of the Wernerian Natural 

 History Society, &c. With Two Plates. Com- 

 municated by the Author, .... 201 



II. On the Precipitation of one Earth or Metallic Oxide 

 by another from Saline Solutions. By John Davy, 

 M.D., F.R.S., London and Edinburgh, Inspector- 

 General of Army Hospitals. Communicated by 

 the Author, 229 



III. On the Origin of Continents. By James D. Dana, 234 



IV. On Sulphate- Chloride of Copper, a new Mineral. By 



Arthur Connell, Esq., Professor of Chemistry 

 in the University of St Andrews. Communicated 

 by the Author, ...... 243 



V. On the Decomposition of Water by Platinum and the 



Black Oxide of Iron at a white heat, with some 

 observations on the theory of Mr Grove's Experi- 

 ments. By George Wilson, M.D., Lecturer on 

 Chemistry in Edinburgh. Communicated by the 

 Royal Scottish Society of Arts, . . . 244 



