Climate and Health in Hot Countries and the Outlines of Tropical Climatology / A Popular Treatise on Personal Hygiene in the Hotter Parts of the World, and on the Climates That Will Be Met Within Them.

by George Michael James Giles

In the matter of choice of site, the same general considerations as to soil and configuration of the ground that determine our choice in temperate climates, as a rule, hold good. A gravelly or sandy soil, and gradients favourable to natural drainage, are even greater desiderata in the Tropics than in Europe, and this is especially the case in climates characterised by a heavy rainfall; but ideal sites are rare in all countries, and as a rule, one must be content to make the best of less favourably placed spots. In the countries which we are at present considering, the especial danger against which we have to guard is always that of malaria, and hence, in choosing the site for a house or station, the great point is to select one, which is, as far as possible, free from natural or artificial collections of water, within a radius of a quarter of a mile; or at any rate, including such only as can be easily filled in, drained, or otherwise dealt with. The site should also be sufficiently raised above the level of some natural watercourse to afford an adequate outfall for its surface drainage.

For a single house, no better position can be selected than the summit of a mound, whether natural or artificial; and such situations are generally to be preferred to the slope of a hill, even where the latter affords a considerably greater elevation. On the sea coast, and not unfrequently in the neighbourhood of some of the great rivers, sand dunes, where sufficiently clad with vegetation to afford a sufficiently stable foundation, form excellent sites for single houses, good examples of which are to be found in Chittagong, where nearly every European residence has its own little hill, on which it is perched by itself; and it is doubtless to this circumstance that the comparative healthiness of the European population of the town, under otherwise unfavourable surroundings, is mainly due. The neighbourhood of jungle, and even of trees, should be as far as possible avoided, for trees undoubtedly harbour mosquitoes, and their presence is generally equivalent to that of malaria: moreover, the appearance of coolness, associated with trees, is deceptive rather than real. As a rule, even when numerous and thickly set, they throw no actual shade on the walls of the house, which hence receives as fully the power of the sun as it would in an open plain, and added to this they obstruct the breeze and generally impede ventilation; so that a house placed in the midst of a glaring, treeless space is often really far cooler than one surrounded with fine timber. Even a garden is by no means too desirable an adjunct to a tropical residence, for unless there is abundant labour to keep it in a condition of perfect neatness, and constant intelligent supervision to ensure that the cultivation of flowers and vegetables be not associated with the breeding of mosquitoes, it is only too likely to originate fever of a luxuriance at least equalling that of its roses and salads.

It must not of course be forgotten, that the provision of a free supply of good vegetables is everywhere an essential to health, and is in many localities obtainable in no other way than by the maintenance of a garden, and that under such circumstances, it is probably safest to keep their cultivation under personal supervision; but where such an accessory is indispensable, its attendant dangers should always be carefully borne in mind, and care should be taken that the garden should be so worked as to avoid its becoming a breeding place for mosquitoes. A house for example, such as that shown in the subjoined sketch, makes, doubtless, a very inviting picture, but when lived in, it would be found that the fine trees almost completely cut off the breeze, that the beautiful creepers render the verandahs and the rooms behind them “stuffy,” and that the wealth of vegetation, combined with the arrangements for irrigation, render it a veritable paradise of mosquitoes.

Fig. 1.—A Regular Mosquito-trap Bungalow.

Coming now to questions of general plan, one of the first essentials is that the floor level should be well raised above that of the surrounding ground. In most localities this object is attained by simply forming a platform of earth dug from some situation hard by, so as to form a plinth; and too often, the excavations for the purpose are made absolutely without plan or method, and result in the production of a number of irregular depressions, close by the habitation; which during rainy weather are always full of water, and form ideal breeding places for mosquitoes, besides too often serving as depositories for refuse. The earth for forming the plinth should, however, never be allowed to be obtained in this way, but previously to laying out the plan of the house or station, a careful survey of the levels and contours of the site should be made, and the alignment of a series of deep cuttings, so designed as to form an efficient system of surface drains extending from the site to the nearest natural effluent, should be laid out, so that the spoil wherewith to form plinths should be taken in a systematic manner in the digging of these cuttings, and from no other situations. The cuttings should be made as deep and narrow as they can be without expensive revetting of the sides, as experience has shown that the larvæ of the really dangerous species of mosquitoes, the Anopheletes, avoid collections of water shielded from the sun and light. As the station develops, it may perhaps become possible to pave these channels with some permanent material, such as brick or concrete, but as a rule the expense of such a proceeding is prohibitory. When, however, a certain amount of money is available for this purpose, it should be devoted to paving the smaller shallow surface drains close to the dwelling, and the deeper distant cuttings close to the effluent left to the last. No house should ever be allowed to be constructed with a plinth of less than one foot, and provided the material be obtainable without making undesirable excavations, it cannot well be too high, a fact well understood by the earlier European residents in India, whose fine old houses, however wanting their work may be in the matter of finish, form an admirable contrast, in this and many others of the essentials of a healthy residence, to the cramped, low-lying heat traps of admirably pointed brickwork in which the occupant of a “sealed pattern” government quarter is now doomed to live.

The writer is personally strongly of opinion that all tropical residences should be at least two storied, so that the sleeping apartments should be raised at least some 12 or 15 feet above the ground, and of course, where this is the case, the provision of a high plinth is less essential, but in any case, the minimum of at least a foot should be insisted upon.

In regions such as Assam and Burmah, where the rains are so heavy as to reduce the entire country to a chronic condition of flooding, any adequate plinth would be so costly that both natives and settlers build their houses perched up on poles, and the numerous sanitary advantages of the plan are undeniable; which is also, I understand, adopted in Honduras.

Fig. 2.—In the above sketch of an ordinary Anglo-Burman bungalow, it will be noticed that the large projecting porch is raised higher than the rest of the house so as to admit of a carriage being driven beneath it to the foot of the steps to the platform of the house. These porches form a sort of open-air sitting room, and are more usually on the same level as the rest of the house. They form a most attractive feature of most Burmese bungalows, but it would be very difficult to protect them against mosquitoes by means of wire gauze.