105
prevalence. If the germs of cholera are wafted over the country by the monsoons,
as insisted upon by Dr. Bryden, I may here ask why it is that in all the cholera
history of Southern India, the inhabitants of this elevated plateau have never
been " struck" by the cholera miasm ?
They have been repeatedly " struck " by the fever miasm, and, indeed, mala-
rious fevers are the most common diseases of natives on the hills. The hill
summits are freely exposed to monsoon influences. Clouds of the south-west
monsoon roll over the hills and envelope them in mist and moisture, and yet
while the people of the Western Coast, and of the country between Salem and
that coast are dying by thousands of cholera, the residents of the hill plateau live
in absolute security.
While I was residing on the Shevaroy Hills in June and July 1865, the inha-
bitants of Malabar were perishing by thousands in a week from cholera. The
south-west monsoon, which blew over this cholera-stricken district, came over
the Shevaroy Hills, enveloping them in its moist air, and yet the only case of
cholera that occurred on the hills was in the person of an East Indian, who had
come up from Calicut on the Western Coast to Salem, the day before, and who
was seized with the symptoms of cholera as he began to ascend the Shevaroy
Hill ghaut. The very remarkable instance of the Shevaroy Hills would seem
to indicate, that if cholera is ever an air-conveyed contagium, the atmosphere
has not the power of lifting it to any great height above the average level of
the land, or of conveying it to any great distance. Cholera may be raging in
the valley between the Shevaroy and Kollamally Hills, and yet fail utterly to
gain a footing on the summit of one or the other range. In the case of the
Shevaroy Hills, although the hill races keep very much aloof from the low
country, there is constant traffic between the town of Salem and the hills.
The road is not adapted for cart traffic, but some hundreds of coolies and
bullocks pass up and down every week. The distance up and down is no more
than a cooly can accomplish in a day, and yet with all this communication with
a frequently infected locality, it is very rare to hear of a cooly dying of cholera
upon the hills.
120. Whatever the true explanation may be, the fact remains that the conta-
gium of cholera, even when brought up by the bodies of travellers, does not
ordinarily spread by multiplication. If the contagium were widely diffused in
the atmosphere during epidemic seasons, it is most improbable that some of the
minute particles of which it is composed, should not be brought over the hills,
exposed as they freely are to the influence of both monsoons. The mere
elevation of the hills above the level of the surrounding country cannot account
for the absence of cholera, because in the case of the Himalaya range, cholera
has been known to prevail epidemically at a much greater elevation than the
highest point of the Shevaroys. The explanation of the difference in the
cholera-producing powers of Salem and the Shevaroys must, I think, be looked
for, to some extent, in the physical differences of the two localities, and also
in the fact that cholera flourishes best in low lying localities, when the subsoil
moisture is never very distant from the surface. (Some facts in regard to Salem
will be found in the Appendix.)