( 35 )
Statement showing admissions from cholera among the European and Native Troops and Jail
Populations in the Bengal Province, together with the strength of the Troops and jails in
the Province during each year of the series from 1854, to 1868 inclusive, and the annual
rate of admissions per mille of strength.


YEARS.
EUROPEAN TROOPS
NATIVE TROOPS
JAIL POPULATIONS
TOTAL
Strength.
Cholera
cases.
Strength.
Cholera
cases.
Strength.
Cholera
cases.
Strength.
Cholera
cases.
Rate per mille of Strength
1854
12,925
110
18,554
467
31,479
577
18.3
1855
12,496
211
16,870
882
29,266
1,013
34.6
1856
3,596
156
14,828
150
16,738
792
35,162
1,098
31.2
1857
?
156*
.....
......
15,930
739
?
895
56.2
1858
5,985
320
....
.....
17,218
711
23,203
1,031
44.4
1859
8,908
290
8,038
97
16,351
686
33,297
1,073
32.2
1860
7,102
329
7,767
137
15,111
1,393
29,980
1,839
62.0
1861
5,890
56
4,420
63
14,939
588
25,249
707
28.0
1862
4,451
24
4,603
41
15,364
367
24,418
432
17.7
1863
4,111
18
6,510
55
13,382
1,072
24,003
1,145
47.7
1864
4,308
20
8,207
89
15,496
652
28,011
761
27.2
1865
4,450
23
9,488
307
16,023
415
29,961
745
24.9
1866
4,381
28
? 9,500
93
18,780
1,415
32,661
1,536
47.0
1867
4,162
7
5,650
65
16,945
363
26,757
435
16.2
1868
3,824
17
7,476
36
16,278
289
27,578
342
12.4
* This number represents the deaths of the year, the number of admissions being unknown.
The presidency hospitals and troops marching-the strengths of which are
not known-are not included in the above statement. The death-rate for
1857 is calculated on the jail returns alone.
The above statement shows that during the four successive triennial periods,
from 1857 to 1868 inclusive, the cholera of Bengal in its general incidence
among the troops and jail populations of the province, has observed a very
remarkable regularity of rise and fall within each triennial period. In the
first year of each triennial period the disease has prevailed with epidemic violence,
during the second it has somewhat abated, and during the third it has sub-
sided to the minimum prevalance of the three-years period, or to the ordinary
cholera prevalence of the province. Thus the epidemic years of the series are
1857, 1860, 1863, and 1866; the ordinary years of the series are 1859, 1862,
1865, and 1868; the intermediate or abating years of cholera of the series
are 1858, 1861, 1864, and 1867. The figures for the first triennial period of
the series, 1854 to 1856 inclusive, do not show the same regularity; this is
probably to a certain extent due to the absence of the returns for the European
troops during the first two years of the triennial period; but it is to be
observed on the other hand that the jail returns taken alone for this three-year
period yielded similar anomalous results. Thus the ratio per mille of strength
of the jail populations in the whole province is 25.2, 47.5, and 47.3 for the
years 1854, 1855, and 1856 respectively; combined with the returns of the
native troops for the first two years of the triennial period they yield the
rates of 18.3 and 34.6 for 1854 and 1855 respectively, and in the third year
of the period, combined with the returns for the European troops also they
yieled the rate of 31.2. Probably the returns for the European troops during
1854 and 1855, were they available, would in a measure restore the regularity of
cholera prevalence in this three-year period and assmilate the results to the
ratios yielded by the succeeding triennial periods of the whole series.
As the figures stand, however, we find that in four out of the five succes-
sive triennal periods comprised between the years 1854 and 1868 inclusive,
there is a remarkable regularity in the rise and fall of cholera activity, and the
regularity is so uniform as to preclude the idea of accidental coincidence.
It would be interesting and important also to ascertain to what extent,
if to any, this regularity in the periodical or cyclical rise and fall of cholera
activity in the Bengal Province is connected with the annual rainfall. But
most unfortunately no data are available to show the characteristics of these
triennial periods in this respect. That there is a real connection between the
annual rainfall and the prevalence of cholera in Bengal, as in the other
provinces of India, there is no reason to doubt. On the contrary, general obser-
vation and popular opinion both strongly incline to the reality of a fixed and
determinate relation between the rainfall and cholera activity; but owing to
the absence of records, it is at present impossible to show what this relation is
F 2