Origin of kála-ázar, etc.

175

In 1874 the fever was noted to be less prevalent in both
Midnapore and Beerbhoom, it never having obtained a sure
footing on the dry, porous laterite soil in the former district,
and in the latter it seems to have turned towards the west,
and to have been checked by the high rocky land of the
Sonthal Parganahs border. Fever was, however, unusually
prevalent in the district of Moorshedabad to the north of
Beerbhoom in both 1873-74, and also in Malda further still to
the north; but it is recorded that this was not an extension of
the Bardwan epidemic, although the Sanitary Commissioner,
Dr. Jackson, who had closely investigated its prevalence in
Bardwan during two years, and written a very full report on
it, to which I shall have to refer presently, seems to have been
somewhat doubtful if it was so or not. It was, however, coin-
cident with a great increase of fever in the still more northern
districts of Dinajpore and Rungpore, and was therefore most
likely due to the seasonal causes that the fever of these last
mentioned places will presently be shown to have been due to.
The further fact that the fever would have had to spread many
times more rapidly than it had ever done in Bardwan in order
to have covered so large an area in one or two years, and that
the type of the fever in these northern districts was differ-
ent from that of the Bardwan epidemic, also support the view
that the latter was independent of the former epidemic.

      Having thus cleared the ground, we are now in a position
to study the great outbreak of fever in the districts of Dinajpore
and Rungpore in the years 1872—79, which also involved
the continuous northern portions of Rajshahye and Bogra.
It is singularly unfortunate that for some of the years when
the fever mortality was highest in the Dinajpore district, no
report was received from the Civil Surgeon in charge, and
that the monthly rainfall in the affected districts has not been
regularly recorded in the Sanitary Reports, as the absence
of full data prevents me illustrating the origin of the epidemic
by a chart made out from the monthly fever-rates and rain-
fall year by year. I will first give one or two quotations to