they
necessarily exposed themselves to many discomforts, which, _caeteris
paribus_, we should be inclined to consider exciting causes of an
infectious or contagious epidemic." We even find that troops have, as
it may be said, _out-marched_ the disease, or rather the cause of the
disease; that is, moved with rapidity over an extensive surface where
the atmosphere was impure, and thereby escaped--on the principle that
travellers are in the habit of passing as quickly as they can across the
pontine marshes. Mr. Bell says, "In July, 1819, I marched from Madras in
medical charge of a large party of young officers who had just arrived
in India, and who were on their way to join regiments in the interior of
the country. There was also a detachment of Sepoys, and the usual number
of attendants and camp-followers of such a party in India. The cholera
prevailed at Madras when we left it. Until the 5th day's march (fifty
miles from Madras) no cases of the disease occurred. On that day several
of the party were attacked on the line of march; and, during the next
three stages, we continued to have additional cases. Cholera prevailed
in the countries through which we were passing. In consultation with the
commanding officer of the detachment, it was determined that we should
_leave the disease behind us_; and as we were informed that the country
beyond the Ghauts was free from it, we marched, without a halt, until we
reached the high table land of Mysore. The consequence was, that we left
the disease at Vellore eighty-seven miles from Madras, and we had none
of it until we had marched seventy miles further (seven stages), when we
again found it at one of our appointed places of encampment; but our
camp was, in consequence, pushed on a few miles, and only one case, a
fatal one, occurred in the detachment; the man was attacked on the line
of march. We again left the disease, and were free from it during the
next 115 miles of travelling; we then had it during three stages, and
found many villages deserted. We once more left it, and reached our
journey's end, 260 miles further, without again meeting it. Thus, in a
journey of 560 miles, this detachment was exposed to, and left the
disease behind it, four different times; and on none of those occasions
did a single case occur beyond the tainted spots." What a lesson for
Dr. Hawkins! But _for whom_ could Dr. Hawkins have written his _curious_
book? Hear Mr. Bell in respect to the common error