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that ankylostomiasis was a disease imported by the Indian 
coolies, practically the whole of our coolie population was 
infected by it, to the extent of 70 per cent. We consequently 
took up as a general measure the necessity of dealing with 
ankylostomiasis; and there is no doubt whatever that if we 
interest agriculturists in this question as a matter of labour 
efficiency, we shall have a very great deal of assistance from 
them on a subject which has been hitherto regarded as simply 
a question of hygiene and one confined entirely to the province 
of medical aid. I am convinced that a large amount of the 
somewhat apathetic disposition of native labourers is due to 
latent disease, which continually depresses their vitality. That 
is the case with regard to malarial fever in the West Indies. 
A great many do not show any active signs of malarial fever, 
but they have malarial fever in their system, and consequently 
are subject to diminished vitality on that account. Malarial 
fever must almost necessarily be dealt with by Government and 
not by local authorities. Any Government which sets to work 
and spends even a few thousand pounds can effect an enormous 
saving in the life of its population and in the health of its 
inhabitants. But we have constantly to be on the watch 
because, as has also been said in the course of the discussion, 
altered conditions will alter the virulence of the disease. We 
found in Jamaica that whereas, in large portions of the 
country, we had considered that we were immune from malarial 
fever, when we sent our labourers down to the Panama Canal 
they contracted there a somewhat different shade of malarial 
fever, from a somewhat different kind of parasite, and when 
they went back to those healthy regions of Jamaica we found 
that they did infect those who had hitherto been immune from 
the local malaria. Owing to such results as that, we are con- 
tinually faced with the question of drainage, and, as has been 
said by a previous speaker, as soon as you begin to cultivate 
hillsides, and set up drains across estates, you at once intro- 
duce malaria into various parts of the country which have been 
hitherto immune, because you set up drains which, although 
theoretically running drains, are drains which collect a certain 
amount of stagnant water in the weeds by the side of them. 
In that respect also we have to bring the planters in to 
take counsel with the Government, and we have had to assist 
them, and show them how to make their drains, and how 
essential it is to their estates to do so in the right way. The 
particular local conditions of the population, and the general 
interest of the public health, are continually interacting upon 
one another. I have nothing more to add, except to say 
generally that I have listened with great interest to what has 
been said, and that I think that our mutual contributions to a 
