Vlil CONTENTS. 



Page 



Proceedings of the Geological Society 541 



Royal Irish Academy 595 



Index 601 



PLATES. 



I. Curves representing the Observations of the Declination and Horizontal 



and Vertical Force Mafrnetometer, at Toronto in Canada during a 

 Magnetic Disturbance on the 23th of September 1841. 



II. Section of a Chart of the South Polar Sea, showing the discoveries and 



track of H. M. Ships Erebus and Terror in a high Southern Latitude- 

 Ill. Illustrative of the Electric Origin of the Heat of Combustion, as in- 

 vestigated by Mr. J. P. Joule. 

 IV. Path of the Moon's Shadow over the South of France, North of Italy, 

 and Part of Germany, during the Total Eclipse of the Sun on July 7, 

 1842. 



Errata. 



In the Supplement, January 1842, vol. xix. page 586, line 4 from the 

 bottom, /or TB read 21. 



Present volume, page 382, line 8, /or " parallel to the ecHptic " tead 

 " in the plane of thermal refraction." 



