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Snow on the Himalaya. 



The same facts are well known likewise at Mussoorie, where the 

 northern slopes are invariably longer covered than any others. It 

 may be said in this latter instance, that the proximity to the plains 

 will not permit the snows to lie long upon the southern exposure, 

 and no doubt this is in a great measure true, but it militates only 

 the more against the arguments adduced by Dr. Lord and others, 

 since according to them, the plains are the cause, or rather furnish 

 the causes, which produce the phenomena they contend for, and 

 which I am endeavouring to refute. The southern course of the sun 

 during the season of snows ought also to weigh in favour of my 

 argument, for it can scarcely ever shine upon the northern face 

 during winter for any length of time ; and certainly only for the short- 

 est portion of the day even in summer ; and, as it is an indisputable 

 fact, that frost commences again in those high regions the moment 

 the sun's rays are withdrawn, or are screened from the northern 

 heights, it stands to reason, and, I repeat, the fact, that the snows 

 should lie longer on the northern, than on the southern exposure. 



Another argument also in favour of the snow on the northern side, 

 appears to be furnished in the occurrence of dense forests and vege- 

 tation along the southern slopes, while they are nearly altogether 

 wanting on the northern face. Whatever may be the cause of this 

 difference, it is certain that where forests and luxuriant vegetation 

 abound, a greater degree of humidity must be engendered than where 

 no vegetation exists, for plants are known to attract humidity ; and 

 again the very occurrence of vegetation must prove a degree of mois- 

 ture in the atmosphere, for without it they could not flourish. Now 

 the damper the climate, the less likely is the snow to be deep, 

 or to lie long, while the drier it is, the less likelihood is there of 

 its melting. Forests, however, not only attract humidity, but exer- 

 cise otherwise a material influence on the districts in which they oc- 

 cur, by raising the temperature and warding olF inclement gales, and 

 therefore snow would continue a shorter time in a well wooded and 

 sheltered country than in one which was comparatively barren. 

 Such should be the case then, in the Himalaya, whose northern and 

 southern aspects correspond in a great measure to such circum- 

 stances. The snows too, are known to melt most readily during the 

 period of the monsoon, when they are dissolved chiefly by the heavy 



