ii CONTENTS. 



Art. VI. On Two Attempts to ascend Chimborazo. By 

 Alexander von Humboldt. Translated from 

 the German, and communicated at the request 

 of the Author, by Dr Martin Barry, - 291 



VII. Meteorological Observations made at Heriot Row, 

 Edinburgh, by a Committee of the Physico- 

 Mathematical Society of Edinburgh. 162 Feet 

 above the level of the Sea. Communicated by 

 the Committee. - - - - 312 



VIII. On the Relations of Natural Philosophy with Che- 

 mistry and the Natural Sciences. By M. Bec- 



QUEREL, . . - . 315 



IX. On Metallurgical Phenomena as illustrative of 

 Geology. By Professor Hausmann of Gottin- 

 gen. Communicated by the Author, - 326 



X. On the Cause of the Temperature of Hot and 

 Thermal Springs ; and on the bearings of this 

 subject, as connected with the general question 

 regarding the Internal Temperature of the Earth. 

 By Professor Gustav Bischoff of Bonn. Com- 

 municated by the Author. (Continued from 

 Vol. XX. p. 376), - - - 330 



Chap. VII Do the llains and other Meteoric Wa- 

 ters cause greater variations in the Tempera- 

 ture of the Soil than in that of the Air, - 330 



VIII — To what depth in the crust of the Earth 

 does the influence of the external Tempera- 

 ture continue to be felt ? . - 339 



IX. — Can it be maintained with certainty that the 

 glaciers are melted from underneath by the in- 

 temal heat of the Earth, and what thermometri- 

 cal phenomena accompany glaciers in general ? 346 



X. — The frozen soil of northern Siberia is no con- 

 tradiction to the increase of temperature to- 

 wards the interior of the Earth, - 377 



XL — The decrease of Temperature in the Waters of 

 the Sea and of Lakes, is not contradictory to the 

 hypothesis of an increase of Temperature to- 

 wards the Centre of the Earth. On the con- 

 trary, we can only explain the Temperature of 

 the Sea and of Lakes by admitting an increase of 

 Temperature towards the Centre of the Earth, »370 



