Sessional_Paper_1901 — Page 437

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Hence it would seem that unless one can cut off, or drain away at once all water which consti- tutes these small springs, to just fill up the pools which they form is but labour in vain, and I am satisfied that it is impossible to effectually drain the whole of the Kennedy Town district, except at considerable cost, although cheap native-made drain-pipes might be laid in a few places with great advantage, nor do I think the training of nullahs would effectually eradicate such breeding-places, as I have recently found Anopheles larve swarming upon the floor of a masonry nullah, even although it has a very good fall, viz. I in 6.

Down this nullah, in common with most nullahs in the dry season, there is now only a very small trickling stream.

In the rainy season when there is a stream of some volume it would be impossible for these larvæ to exist there.

As however I mentioned in a paper read before the South China Branch of the British Medical Association on April 2nd last, when reporting the discovery of the Anopheles mosquito in the Colony, I think much good might be done by the judicious application during the dry season of various insec- ticides such as Kerosine, Jeyes' Fluid, Gas Tar and the like to the pools which form its breeding-places and this might easily be effected for the district in question by detailing an intelligent coolie for the purpose under the supervision of Inspector Watson, who is well acquainted with this mosquito and its larvæ, he being first associated with me in the discovery of the insect's habitat.

Had this plan been adopted at the commencement of the dry season, and all pools in the district been so treated periodically up to the present time, there would now remain very few of the Anopheles larvæ in the neighbourhood, and this might have been accomplished at a comparatively small cost.

From continual observation I am satisfied that this, combined with such surface drainage as may be practicable, is the only method which will ever keep down the Anopheles pest in the Kennedy Town district, and I am not at all sure that even this plan would be entirely successful as all kinds of mos- quitos multiply at a prolific rate. It would however go a long way towards having the desired effect.

Native Staff-During the year the Chinese in the department received a substantial increase of pay, although I regret that nothing has so far been done to improve that of the European subordinate staff.

I have the honour to be,

The Acting Secretary,

SANITARY BOARD.

Sir,

Your most obedient servant,

C. VIVIAN Ladds.