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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 



