India and Indian Engineering. / Three lectures delivered at the Royal Engineer Institute, Chatham, in July 1872

by J. G. Medley

Now to apply these facts to our subject.

As a mere question of comfort, it has been found that a building constructed with walls of mud or sun-dried brick, with a good verandah all round, and with a thick roof of thatch, is certainly the most comfortable. It is cooler in the summer, warmer in the winter, and a good thatched roof is perfectly water-tight. But such a roof is always exposed to danger from fire, and both roof and walls require perpetual repair in the rains; while those Indian pests, the white ants, besides snakes and other vermin, increase and multiply to an alarming extent in such a building. Stone is scarce and expensive, except in a few localities, so brick is the material usually employed for permanent buildings, and the thatched roofs are replaced by tiles or concrete. Such buildings, however, become insufferably hot during the day, and numerous doors and windows are provided to allow a sufficient volume of cool air to enter during the cooler hours of the night; they give rise to one of our chief difficulties, for, during the whole of the hot weather, these openings must be kept closed for ten or twelve hours at least, to exclude the heated external air, and if so closed, some special means of ventilation ought certainly to be provided.

It is not, however, easy to effect this, for the simple reason that the air inside the building is cooler, and therefore heavier, than that outside, and thus will not pass out easily by apertures above, which also generally admit quite as much dust as fresh air.

As these numerous doors and windows evidently give access to a great deal of heat, even when closed, it seems desirable to enquire whether fewer openings would not be a better arrangement, and there can be little doubt that this would be the case, if a proper system of ventilation were at the same time contrived by blowers, or otherwise, as will be hereafter noticed. It is also probable that thicker walls of hollow bricks, or even double walls, would be a great improvement over the present thin walls of solid brick. But brick-making machines are still in their infancy in India. The tiled roofs are also doubtless a great cause of the heat of these barracks. And as thatch is out of the question, it seems very desirable to find some non-conducting, non-inflammable substance, which should be interposed between the tiles and joists.

It may be noted that, amongst the natives, underground apartments are not uncommon, to escape the great heat of the summer. In the fort at Lahore, an extensive system of such tykhanas (as they were called) was found on our capture of the place, and they were certainly much cooler than the rooms above ground; but the difficulties of providing proper ventilation and light would be great, and they would probably not be healthy for Europeans.

The subject of what is the best description of building, both as to design and materials, for Europeans in such a climate as India, is indeed still an open one, and admits of great discussion. Neither our barracks, churches, nor private houses are as yet satisfactory, and as to their architectural appearance, the less said about that the better. The Gothic churches generally built in our Indian stations are insufferably hot. In that at Mean Meer, it was not uncommon to hold the service, even in the early morning, outside the church and under its own shadow! Most of the private houses in the various cantonments are simply hideous, and even the best of our public buildings, law courts, town halls, &c., are anything but adapted to the climate. Imitations of Classical, Italian, and Gothic architecture are plentiful everywhere, but few attempts have been made to adapt any of the features of Oriental architecture to our Western requirements. Yet who can gaze on the beautiful domes and minarets of the Taj Mehal or the Jumma Musjid, or the graceful arches and bold cornices of the Motee Musjid, without admiration and envy? It is much to be desired that the whole subject should be taken up and carefully studied; but so long as we have so little originality even in England, we must have patience in India.

To return to our barracks. During the hot season, the air inside is rendered more bearable by the employment of punkahs or pendant fans, which, being swung from the roof and pulled to and fro by manual labour, afford a very grateful relief, though, of course, they do not really lower the temperature of the air. Besides this, during the dry heat, tatties, or screens of grass, are hung in some of the doorways to windward, and, being kept saturated with water, fresh air is thus introduced, which is often, during a strong breeze, from 10° to 20° below the external temperature. But this contrivance is of course useless during the rainy season, when the external air is already saturated, and when often there is not a breath of wind stirring.

About three years ago a committee, of which I was a member, was appointed at Roorkee to consider the question of ventilating and cooling barracks and other public buildings in India. It was pointed out that the present arrangement of punkahs and tatties cost Government annually a very large sum; that the results were not believed to be at all commensurate with the cost, and that it was desirable to see what improvements could be introduced.

Many interesting experiments were made, both as to the best modes of hanging and swinging punkahs, and as to the possibility of dispensing with them altogether by using blowers, similar to those employed for ventilating mines, which are to some extent already used in India under the name of thermantidotes. It was found that a system of blowers, with tubes for conducting the air into the barrack-rooms, would certainly be useful for the purpose of ventilation, but that they would not enable punkahs to be dispensed with, for they could not produce the same sensation of coolness as a punkah, except by keeping the whole body of air in the room in movement at an extremely rapid rate by an extravagant expenditure of power, or by throwing cooled air in, in sufficiently large masses, as in the case of a tattie with a strong breeze blowing. Now, although it was easy to produce the breeze artificially during the dry heat, it was of no use during the rainy season, unless some artificial means could be found of cooling the air otherwise than by evaporation. And there appears no means yet known to science of effecting this in such quantities as are here required, and at such a cost as will not be ruinous. It is true that many schemes have been proposed, and some tried successfully, on a small scale, such as the use of ice, ether, ammonia, &c.; also condensing machines, such as Dr. Arnott’s; but it is believed that the problem has never been solved on a large scale yet.

Of course, the utility of blowing in fresh air for ventilating purposes is not questioned. It has been carried out in several public buildings lately erected in India; but to blow it in even during the three hot dry months, in such quantities as to cool, as well as ventilate, the whole interior of a large barrack, is expensive work; for a whole set of barracks, comprising from fifteen to thirty different buildings, separated from each other by considerable intervals, several steam engines and an enormous quantity of tubing would be required; and the cost of such things in India is almost ruinous.