well from which the water is taken is kept in good condition. Very few people, however, take such precautions to keep the water pure. Hence the best way of removing the impurities of the water is to boil it well, and, after cooling it, filter it carefully into another vessel through a thick and clean piece of cloth. Our duty, however, does not end with this. We should realise that we owe a duty to our fellowmen in this matter. We should see to it that we do absolutely nothing to defile the water which is used for drinking by the public. We should scrupulously refrain from bathing or washing the water which is reserved for drinking; we should never answer the calls of nature near the banks of a river, nor cremate the dead bodies there and throw the ashes after cremation into the water.
In spite of all the care that we may take, we find it so difficult to keep water perfectly pure. It may have, for instance salt dissolved in it, or bits of grass and other decaying matter. Rain water is, of course, the purest, but, before it reaches us, it generally becomes impure by the absorption of the floating matter in the atmosphere. Perfectly pure water has a most beneficial effect on the system; hence doctors administer distilled water to their patients. Those who are suffering from constipation are appreciably benefitted by the use of distilled water.