ose which take place immediately before the rains,
after the cold and dry seasons, to bad water. The same petrolium, or
liquid bitumen, is found floating on the spring waters in the hot
season, when the most fatal diseases break out in the jungles, about
the sources of the Nerbudda and Sohun, as in the Oude Tarae; and, in
both places, the natives appear to me to be right in attributing them
to the water; but whether the poisonous quality of the water be
imparted to it by bitumen from below, or by the putrid leaves of the
forest trees from above, is uncertain; the people drink from the
bituminous spring waters at this season, as well as from stagnant
pools in the beds of small rivers, which have ceased to flow during
part of the Cold, and the whole of the hot, season. These pools
become filled with the leaves of the forest trees which hang over
them.

The bitumen, in all the jungles to which I refer, arises, I believe,
from the _coal measures_, pressed down by the overlying masses of
sandstone strata, common to both the Himmalaya chain of mountains
over the Tarae forest, and the Vendeya and Sathpoor ranges of hills
at the sources of the Nerbudda and Sohun rivers. It is, however,
possible that the water of these stagnant pools, tainted by the
putrid leaves, may impart its poison through the medium of the air in
exhalations; and I have known European officers, who were never
conscious of having drunk either of the waters above described, take
the fever (owl) in the month of May in the Tarae, and in a few hours
become raving mad. These tainted waters may possibly act in both
ways--directly, and through the medium of the air.

While on the subject of the causes or sources of disease, I may
mention two which do not appear to me to have been sufficiently
considered and provided against in India. First, when a new
cantonment is formed and occupied in haste, during or after a
campaign, terraces are formed of the new earth dug up on the spot to
elevate the dwellings of officers and soldiers from the ground, which
may possibly become flooded in the rains; and over the piles of fresh
earth officers commonly form wooden floors for their rooms to secure
them from the damp, new earth. Between this earth and the wooden
floor a small space of a foot or two is commonly left. The new earth,
thus thrown up from places that may not have been dug or ploughed for
ages, absorbs rapidly the oxygen from the air above, and gives out
carbonic a