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TIBET. 
the disease and situations, where it is common, had been the subject of 
inquiry, or awakened the attention of any able practitioner, we should 
have been long since undeceived in this respect. On the coast of 
Greenland, the mountainous parts of Wales and Scotland, where 
melted snow must be continually passing into their rivers and streams, 
the disease is not known, though it is common in Derbyshire, and 
some other parts of England. Rungpore is about one hundred miles 
from the foot of the hills, and much farther from the snow, yet the 
disease is as frequent there as in Boutan. In Thibet, where snow is 
never out of view, and is the principal source of all their rivers and 
streams, the disease is not to be met with; but what puts the matter 
past a doubt, is the frequency of the disease on the coast of Sumatra, 
where snow is never to be found. On finding the vegetable produc¬ 
tions of Boutan the same as those of the Alps, in almost every in¬ 
stance, it occurred to me, that the disease might arise from an impreg¬ 
nation of the water by these plants, or the soil probably possessing 
similar qualities, the spontaneous productions of both countries, with 
very few exceptions, being so nearly alike. It, however, appears 
more probable, that the disease is endemial, proceeding from a pecu¬ 
liarity in the air of situations in the vicinity of mountains, with such 
soil and vegetable productions. I am the more inclined to think so, 
as I have universally found this disease most prevalent amongst the 
lower class of people, and those who are most exposed to the un¬ 
guarded influence of the weather, and various changes that take place 
in the air of such situations. The primary cause in the atmosphere 
producing this effect, is perhaps not more inexplicable, than what we 
