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of epidemic malaria similar to that which has occurred at Hong Kong,
Panama, and many other places in the tropics. And if we follow, as
closely as possible, the course of fever epidemics in those years
when they have been widespread and intense we find that they cor-
respond in an extraordinary manner with the times and places in
which industrial projects or large public works were being most ac-
tively pushed forward.
A special period characterised by the prevalence of epidemic
malaria coincident with an expansion in the coal trade and the con-
struction of great public works may be recognised in 1860·74, and
another in 1880-81 when, after times of lessened activity, numbers
of important and long postponed projects were put in hand,
and it is recorded that the expenditure on railways, irrigation works
and roads amounted to the sum of 20 crores of rupees within a few
years.
As the Presidency became opened up, its railways extended, its
canals completed, and its up-country industries developed, the series
of malarial epidemics assumed a new phase and Dinajpur and Rung-
pur, which a glance at the map will show stand at the portals of the
tea districts, and Rajshahi, which lies immediately to the south, begin
to be conspicuous as the seat of epidemic malaria. Reference to the
Census reports will show that there has, been no more extensive emi-
gration in India than that which has taken place from the south-west-
ern portions of Bengal and part of the adjoining provinces to the
tea gardens in the north-east. All the main lines of communication
pass through the areas we have mentioned, which are covered with a
network of roads and railways pushed forward, especially in Dinaj-
pur and Rungpur, to meet the growing exigencies of the tea and jute
industries; for until comparatively recent times vast numbers of emi-
grants travelled to their destination on foot or at least traversed con-
siderable tracts of country in this way. We have had an opportunity
of seeing some portions of this tract, including Dinajpur, and, though
we have not been able for want of time to study the conditions
closely, we find everywhere growing in the bazars and outskirts of the
smaller towns the characteristic little aggregations of immigrant