53
From this table we may summarise the following particulars :-
Months.          
Cholera Deaths.
                
DEATHS IN VILLAGES ON


River Banks.
Higher Ground.
January 
8
2
6
February
45
35
10
March   
243
219
24
April 
637
454
183
May     
1,721
1,289
432
June
1,911
1,038
873
Total...
4,565
3,037
1,528
When we come to consider how few rivers there are in the district, and 
reflect on the enormous excess of mortality in the river valleys, as compared 
with that of villages on higher ground, we are enabled to understand in some 
degree what Pettenkofer means by asserting that there is a fixed relation 
between the development of cholera and the distance of sub-soil moisture from 
the surface.
Floods in Tinnevelly 
in November 1869.
Year.		Inches.
1866		19.98
1867		17.81
1868		15.95
NOTE.-These averages
are computed from 
eight district rain re-
gisters.
74. Now, in regard to the unusual prevalence of cholera in the Tinnevelly Dis-
trict, and especially those portions of it that had been recently 
subjected to inundation, it must be noted that, in November 
1869, a cyclone passed over the district, discharging an unusual rain-fall, which 
flooded the river valleys, and tended to raise the level of the sub-soil moisture 
greatly beyond its normal height. The average rain-fall for the whole district in
the north-east monsoon of 1869 was 26.44 inches, and the greater part of this
fell during the great storm of November that flooded the country. The average
rain-fall of the three former years in October, November, and 
December was as in the margin. It will be seen that the mean 
rain-fall of the district, during the three months of the north-
east monsoon, is between seventeen and eighteen inches, 
while in 1869 the quantity was nearly ten inches in excess.
The difference, in fact, was quite sufficient to cause a very perceptible 
change in the level of the sub-soil water in the valleys and low lying grounds 
of the district, for the early part of the year 1870; but the exact nature of the 
changes, and their relation to cholera, cannot be shown as no observations 
were made in the district for testing Pettenkofer's theory.
75. The progress of cholera in the district does not appear to have been 
influenced by the monsoon winds. It began, as we have seen in February, at the 
end of the north-east monsoon. It advanced southward in the months of March, 
April, and May, against the strong southerly winds that prevailed in those months, 
and the epidemic abated, or began to abate, in the middle of the south-west 
monsoon winds, and by the end of September the primary epidemic had lived 
out its life. The south-west monsoon continued to prevail in 1870 up to the 
middle of October. In December there was a reproduction of cholera in this 
district, the history of which will more properly fall to be noted in the cholera 
report for the current year.