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decision upon this important matter, but it may be said that, as a general
rule, in every place which is entitled, or hopes to be entitled, to be called a
"town" measures for the suppression of mosquitoes should be begun and
carried on from year to year regardless of any difficulties that may be met
with. As a general rule also it may be said that in villages we should not
attempt the measure unless the conditions which cause the prevalence of
mosquitoes are obviously very easily remedied-in which case the village
would not, in all probability, be malarious-and as regards Indian canton-
ments we may say (again as a general rule) that the number of soldiers
present in them during the malarious season of the year is usually so small
and the area of ground covered by the cantonment is usually so large that
simpler and in the circumstances more efficacious measures are indicated in
preference to the attempt to suppress Anopheline mosquitoes.*
Turning now to the measures required for the suppression of these insects
we know that Anopheline and other kinds of mosquitoes are much more easily
dealt with in their larval condition in water than in their adult state. The
main object of all efforts directed to the suppression of mosquitoes is therefore
to get rid of all places where they can breed. This is comprised in the words
" effective drainage." From the earliest times it has been recognised that
malaria may be diminished, and in some places banished, by drainage and
drying of the soil. It is probably by these means chiefly that large tracts of
country in England, Holland, France, and many other places which formerly
were very malarious have been rendered healthy and productive. It is also
for this reason that large towns such as Rome in Italy, Calcutta, Bombay and
Madras in India, are far less malarious than the outlying villages which sur-
round them, though in the latter cities a great deal in the way of effective
drainage still remains to be done. In our towns in India, in proportion
as we effectively prevent the formation of stagnant pools of water, and
in proportion as we carry out measures for drying the soil and lowering
the level of the sub-soil water, so will the number of malaria-bearing
mosquitoes and in consequence the prevalence of malarial fevers,
diminish.
* In Mian Mir, for example, about 800 European and 1,700 Native soldiers are
distributed over an area of 8,661 acres or 131/2 square miles.