178

Report on Kála-ázar.

    It is further stated that—

"there is no material change in the country to which the
prevalence of this fever could be traced; and the most probable
cause to which it could be ascribed is climatic influences, viz .,
scantiness of rain and excessive heat, which intensified and con-
centrated the marsh poison."

That this is the true explanation is proved by the fact that
a study of the monthly rainfall and fever-rates in both
Dinajpore and Rungpore from 1881 to 1894 shows a most
definite relationship between a low rainfall, especially if it is
also irregularly distributed so as to cause alternate flooding
and drying up of the land, and an increase of the fever-rate.
Moreover, in the years 1873, 1875, and 1877, in addition to
the rainfall being much below the average in Dinajpore and
Rungpore, in every case it was very irregularly distributed.
For instance, in the year 1873, the monthly rainfall in Rung-
pore was as follows:—In the first three months only 1.2 inches
fell, in April there were 8.24 inches, in May 1.07, in June
13.09, in July 3.93, in August 14.11, in September 2.63, and
none in October or November, and but 0.38 in December,
the total being 44.64 inches, or barely half the normal average,
which was 88.19 for the five years previous to 1873; so
that there must have been a succession of floods followed by
the exposure and drying up of the saturated soil under a May,
July, and September sun, than which no more favourable cir-
cumstances can be imagined for the multiplication and escape
into the air of the malarial organisms by their being
carried up in the evaporating moisture. When we see a series
of such years one after the other, is it any cause for wonder
that fever should become more and more prevalent and intense
until an epidemic of malarial fever is produced? Is it surpris-
ing that in this year it is recorded of the fever in Rungpore
that—

       "From May to December it continued increasing in intensity, so
that the majority of the population were completely prostrated by
repeated attacks of the disease?"

     In this connection the Civil Surgeon's description of the