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

A single metal vessel and rope should be provided, which should never be removed from the well-house, and no other vessel should be permitted to be lowered into the well on any pretence; for the practice of each person carrying about his own drinking vessel and string provides the mechanism whereby cholera is carried from one place to another in the majority of outbreaks of that disease in India. If possible, only a single servant should be employed to draw water, and he should be provided with a padlock and instructed to keep the door locked. Very probably the door will often be left open, but it is something gained if it be locked for some hours in the day, as the fact of finding the door even sometimes locked will serve to show outsiders that the use of the well by them is regarded as a trespass.

Provided that the entry of leaves and other even more objectionable matters be prevented in this way, a well should require but little attention, though it may be useful to occasionally purify it, especially if it has been out of use for some time, by treatment with permanganate of potash in manner described below.

Where a well is persistently foul, it may be taken as certain that this is due to prolonged neglect and insufficient cleansing; for when, as is usually the case, no attempt is made to guard a well, so much dust and rubbish of all sorts gain admission that it requires to be emptied and thoroughly cleaned out, down to the soil in which it is excavated, at least once a year, and the expense of doing this will be found to be at least as great as the construction of a well-house of inexpensive materials. When the water of a well has been obviously offensive, the actual soil at the bottom of the well should be dug out for two or three feet, and fresh, clean river sand substituted. After the well has refilled, it should be treated once or twice with permanganate, and the water will then usually be found to be restored to good condition.

To purify a well by means of permanganate of potassium, take from 2 to 4 ounces of the chemical, according to the size of the well, the larger quantity being required only in the case of the enormous wells 10 to 12 feet wide that are occasionally met with; draw a bucketful of water and dissolve the permanganate in its contents by stirring with a stick. Lower the solution into the well, and flounce the bucket about in the water till the permanganate is thoroughly mixed. Permanganate attacks the organic matter present in the water, on which the disease germs and other micro-organisms feed, and so kills them by starvation, besides which the brown precipitate which is formed carries down with it much suspended matter. This process is of especial value in destroying the cholera microbe, and when moving about in camp, it is an excellent precaution to send on a man two days in advance to disinfect in this way the wells that will be used in each camp. If the amount of permanganate used be sufficient, the water should still retain a faint pink tinge after twenty-hours, and should have another day’s rest to settle before being again taken into use. The purer the water, the longer will the pink tinge persist, while on the other hand, the rapid disappearance of the colour is an indication of great foulness, and of the necessity for the application of a further supply of permanganate.

The water of large rivers is usually fairly reliable, provided the water be got from the full current and not from a backwater, but is often very turbid from fine sand and other mineral matter. In such cases, the water may be cleared by stirring it round with a crystal of alum; after which the suspended mineral matter will sink to the bottom in the course of an hour or so. The manner in which the alum acts is not clearly understood, as the amount dissolved is so small as to be insufficient to affect the taste of the water or to do any harm, even if it be consumed for a long period. The action of the alum, too, is far more efficient than that of any ordinary filter, completely clearing glacier-fed water turbid with particles of such extreme fineness that they will pass anything except the biscuit-porcelain, or Pasteur, filter. Alum may also be used for disinfecting wells when permanganate is not obtainable, about twice the weight of alum being used, but it is not as reliable; and in case of need, lime may be used, 40 or 50 lbs. of well-slaked lime being thrown into the well, and thoroughly mixed with the water by keeping it disturbed for some time.

The water of small pools and marshes should be avoided, and even springs should be regarded with suspicion, unless some idea can be formed as to the origin of the water. If this be from a deep source, it may of course, be safely used, but care must be taken not to mistake surface drainage that has oozed a short distance under ground for a true deep spring. Caution in this matter is especially necessary in hill country; and in doubtful cases it is well to get water analysed by an expert before adopting it as a permanent supply, for it is noteworthy that some springs of the highest reputation have been shown to be extremely impure, the sparkle of their waters being really due to their being charged with the gases of decomposition.

Not unfrequently, however, the tropical sojourner has no choice as to his water supply, and must make the best of perhaps a very bad source. Under such circumstances, all water used for drinking, or in the preparation of food, must be specially treated so as to remove or destroy any of the germs of disease which it may contain. It is desirable, though very difficult, to treat water used for bathing in the same way, but as a rule, one has to be content with taking every precaution against such water entering the mouth.

Ordinary filters, it must be clearly understood, are not only useless, but even worse; for the moist filtering agent, clogged as it is with the coarse organic and inorganic débris that it has strained out of the water, is quite capable of acting as a cultivating medium for microbes, on which they can multiply so enormously that however clear the water may appear to the eye when it issues, its really dangerous impurity, so far from being diminished, has been enormously increased. There is only one form of filter that can be trusted to remove the minute organisms that are the active agents in the propagation of disease, and that is that in which the water has to pass through a piece of biscuit porcelain, the pores of which are so excessively minute that even the smallest of the bacteria are excluded. The employment of such filters on a domestic scale is, however, extremely difficult, for they naturally act so slowly that a very large appliance must be used to secure an adequate supply. Added to this, their efficiency depends on the perfection of a number of rubber connections, a material which deteriorates very rapidly in hot climates, and except by the increased rapidity of flow, it is not very easy to detect the fault. In any case, they should never be used except under constant personal care, and one way and another, they require a good deal of attention; besides which they are heavy, and quite unsuitable for camp or travelling. On the other hand, boiling for a few minutes gives a security quite sufficient for practical purposes, and requires no more formidable appliances than an ordinary kettle or saucepan, which are available everywhere. I am perfectly aware that certain spores will sometimes survive the treatment recommended, but the objection is rather academical than real, and so far as I know, in the actual practice of daily life no instance of the conveyance of disease has ever been traced to the use of boiled water, so that I have always been accustomed to recommend the adoption of this plan in preference to all others, in all cases where the water supply is not absolutely above suspicion.

One caution, however, is necessary: always personally to see that the water boils; for, apart from absolute deception, servants often really do not know when water has actually reached the boil, as most housewives know from experience of the spoiling of their “dish of tea.”

There is no need to stand over the man and watch the process however. A portable stove should be brought into the verandah, and the servant should be instructed to let one know when it is boiling, so that a moment’s inspection suffices to satisfy one of the fact, which, after all, is not a very formidable addition to the day’s work.