324 Lieutenant R. Strachey on the 



land Head, about fifteen miles distant, yielded, as already 

 remarked, only 4 per 10,000, part of which was sulphate, 

 part carbonate of lime. 



By certain management, I am informed, as by not allowing 

 the sea-water in the boilers to be concentrated beyond a 

 certain degree, the incrustation, in the instances of the 

 transatlantic steamers, is in a great measure prevented. 

 Perhaps it might be prevented altogether, were sea-water 

 never used but with this precaution, and taken up at a good 

 distance from land, and in situations where it is known that 

 the proportion of sulphate of lime is small. If this sugges- 

 tion be of any worth, further, more extensive and exact in- 

 quiry will be I'equisite to determine the proportion of sul- 

 phate of lime in different parts of the ocean, and more espe- 

 cially towards land. By the aid of the Transatlantic Steam 

 Navigation Companies, means for such an inquiry may easily 

 be obtained ; and it can hardly be doubted that the results 

 will amply repay any cost or trouble incurred. — {Proceedings 

 of the Boyal Society of London, March 29, 1849.) 



Oti the Snow-Line in the Himalaya. By Lieutenant R. 

 Strachey, Engineers. Communicated by order of the 

 Honourable the Lieutenant-Governor, Noi*th-Western 

 Provinces of India. 



The height at which perpetual snow is found at diflFerent 

 parts of the earth's surface, has become an object of inquiry, 

 not only as a mere physical fact, but as a phenomenon inti- 

 mately connected with the distribution of heat on the globe. 

 In M. Humboldfs efforts to throw the light of his knowledge 

 on this question, he has, when treating of the Himalaya, been 

 unfortunately led much astray by the very authorities on 

 whom he placed raost reliance; and his conclusions, though 

 in part correct, cannot lay claim to any pretension to exact- 

 ness. That he was, indeed, himself conscious of the defi- 

 ciencies in the evidence before him, is manifest from his end- 

 ing his disquisition by a declaration, that it was necessary, 



