420 



Proceedings of tho London Electrical Society. Part 8. — By the 

 Society. 



Annual Report of the Council of the Yorkshire Philosophical So- 

 ciety, for 1842. — By the Society. 



Elements of Agricultural Chemistry. By Sir Humphrey Davy, 

 Bart. (Sixth Edition.) — By Dr John Davy. 



Proceedings of the Royal Astronomical Society. Vol. V. No. 29. 

 — By the Society. 



Proceedings of the Royal Society. Nos. 55 & 56. 



Revised Instructions for tho use of the Magnetic and Meteorological 

 Observatories, and for tho Magnetic Surveys. Prepared by 

 the Committee of Physics and Meteorology of the Royal So- 

 ciety. — By the Royal Society, 



Monday, \st May 1843. 

 Sir T. M. BRISBANE, Bart., President, in the Chair. 



The following Communications were read : — 



1. An attempt to explain the Phenomena of the Freezing 

 Cavern at Orenburg. By Dr Hope. 



Dr Hope in the first place read, from the Proceedings of the Geo- 

 logical Society in London, the account of the freezing cavern fur- 

 nished by the President of the Geological Society of London. This 

 is one of several caves which exist in the southern face of a length- 

 ened low hillock of gypsum. It is entered from the south by a pas- 

 sage rather narrow, and is about fifteen feet high, ten paces long, 

 and seven wide, which seemed to send off irregular fissures into the 

 body of the rock. 



The extraordinary feature of this cavern is, that during summer 

 it is so cold that ice is generated in it, and dry icicles hang from its 

 roof ; and that, in winter, all appearance of congelation ceases, and 

 the temperature becomes such that the Russians say they could sleep 

 in it without their sheep-skins. 



Mr Murchison applied to Sir John Herschel for an explanation, 

 and the theory which he proposed is, that the heat and cold of the 

 surface gradually move, though very slowly, backward into the rock ; 



