Chapter III.]

PHENOMENA ATTENDING THE RE-APPEARANCE OF CHOLERA IN 1875.

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revives. But I see nothing improbable in the suggestion that cholera may be distributed in
its dormant state as well as in its vital condition."

       These were the circumstances which induced me to attach so great an importance to the
first case in our types that showed itself in the epidemic area of Upper India in succession to
the epidemic of 1872; and to report to the Sanitary Commissioner that I associated the occur-
rence of this undoubted case of cholera, which, as before mentioned, occurred at Lullutpore
on 28th October 1874, with renewed epidemic distribution, the extent of which was to be
determined only by the spring manifestations of 1875.

   The cholera of the endemic area
preceding and accompanying the
new cholera of 1874-75.

       Was there evidence of the presence of a body of cholera
epidemic within the endemic area sufficient to account for an
overflow involving Western and Northern India ?

       These figures show that in the last ten days of October, the exact date at which endemic
cholera is due to come forward after its annual disappearance, a great epidemic commenced;
and 60,000 deaths were registered in Bengal Proper before the middle of 1875, and 116,606
in all before the end of the year, against a total of 57,000 in 1874.

       The culmination in Lower Bengal of the spring cholera of March and April I take to
be the homologue of the simultaneous culmination in the Gangetic Provinces and in Oudh
already shown, the cholera being of one and the same growth. And I take it to have been the
very same material which became evident in Ceylon in January, February and March, and
in Southern, Western and Northern India in the middle of April; which, over certain areas,
was fostered into epidemic strength in May, and was in others anchored down until set free
with the advent of the monsoon after 20th June.

RISE OF CHOLERA WITHIN THE ENDEMIC AREA FROM OCTOBER 1874 ONWARDS.

       Cholera Deaths of Bengal Proper, September 1874 to August 1875.

   General conclusion regarding the
primary distribution of the epidemic.

       In its own breeding grounds cholera has the power of manifestation in October, November
and December; beyond the endemic area this power of mani-
festation is lost or impaired. And although cholera may be
epidemically spread in October as well as in spring or during
the monsoon season, the material so diffused is inert or comparatively inert, until certain in-
fluences cause it to come into manifest life, earlier or later according to the situation occupied,
but at dates fixed and normal for each province and locality. And the inference we draw is,
that the great fan-shaped area, of which Eastern Bengal is the handle, and the line occupied
by the spring cholera of 1875 the circumference, was covered in the last months of 1874 by
a cholera which lay dormant until 15th April.

       Over the area marked out by the spring cholera, after the middle of October blows from
Northern and Eastern Bengal, the north-east monsoon. As I write, on 20th October 1877, its
burst for the year is announced. In his report for 1875, the Sanitary Commissioner for the
Central Provinces writes: "The wind changed to the north, and in the third and fourth weeks
of October rain fell generally over the province. Through October, November, and December
the prevailing wind was from the north-east, which is the normal direction at that season of
the year." And the report for the last weeks of October 1874—the presumed date of distri-
bution of the cholera of 1875, was the same: "North-westerly winds continued through the
early part of October, but in the latter end of that month the wind veered more to the east,
and took up its normal quarters for the cold weather, which are north and north-east." And
we read that in the eastern districts of the Central Provinces, which so powerfully localised the
spring cholera of 1875, the weather continued cloudy and moist through the month of Octo-
ber. Given the material of an epidemic, here is indicated the vehicle for its conveyance, and
its limits are but the limits of the same air-borne influence. A cholera thus geographically
deposited is placed so that when the south-west monsoon gives it life and motion its
advance is from the south-west; and we are prepared to find in the monsoon season of 1875
great and sudden movement on vast tracts within the area of the fan, absolutely unoccupied
before the manifest occupation of July and Auugst. These were the movements spoken of
in former times, and constantly cited even now, as advances in the teeth of the south-west
monsoon, and which I have all along maintained to have been apparent only and not real.
The natural history of cholera is a consistent history, and it is our fault if we fail to unite into
a harmony every fact connected with its manifestation.

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