1868.] Water. 399 form this duty, should be closely watched and held strictly accountable, in view of the health of an immense community, which the3 r actually watch over, and which is dependent on them. For, the purer the Water the surer the Health, may be taken as the maxim, which should invariably govern the management of water-works. We will now turn our attention to those of our citizens, outside the in- fluence of water-works, either residents of the suburbs, or dwellers in the coun- try. In case there should be a difficulty, in obtaining water fit for drinking purposes, by the sinking of wells, as frequently is the case, it would be well to have a capacious cistern, with a filtering com- partment, which would receive all the rain-water from the roof, provided that the roof is not of lead, and has not sol- dered joints. Such a cistern should be constructed on principles of strength, durability, and sanitary precaution. Strength does not, in the making of cisterns, necessarily involve durability, the latter being de- pendent on the material of which the cistern is constructed ; and that mate- rial must be such, as to give resistance to the decay, which is the consequence of exhalation and corrosion. In case the cistern is covered in with boards on joists, exhalation is sure to work slow, but certain ruin ; and this fact can scarcely be too well noted, where it is proposed, as is often the case, to put a cistern in the cellar-basement, for the convenience of having a small pump in the kitchen or laundry, above it. In such case, also, it should be borne in mind, that water, covered in, will turn foul quickly, from the fact of its mephitic gases, having no means of escape, settling down on and impreg- nating the surface, thus generating ani- malcule, whose decomposition is so destructive to the purity of water. Such a condition of things is abundantly pro- ductive of that troublesome little atten- uity, the sanguinary mosquito ; and, supposing such cellar cisterns to be left uncovered, the same consequences arise ; and the floor above it becomes con- stantly damp, and speedily rotten. Added to which, the damp air pene- trates the upper part of the house ; and superinduces those fatal pulmonary and bronchial affections, which are the more deplorable, as arising from a source, so thoughtlessly created. Lime should not take a prominent part in forming the lining of cisterns, as its effect is, to harden the water ; and unfit it for domestic purposes. Cement, or, as it is often called, water-lime, on account of its property of setting under water, is found to be an excellent lining for cisterns. But the first filling of water should be pumped out, and the cistern, when thoroughly hard, carefully cleansed. Brick makes a good lining for some years ; but its porousness is apt to admit external influences ; and absorb and retain, internally, those objectionable substances held in solution ; and, conse- quently, offers an impediment to cleans- ing the cistern. Zinc lining, for large cisterns, is good ; but, like that best of linings — iron — is too expensive, for general use. Wood is not to be recommended ; as, apart from its decaying propensity, in large surfaces, it gives a peculiar, and not agreeable flavor to water, quiet so long as cistern water is liable to stand, not to speak of the vermiparous propen- sities of such material, when so used ; unless, indeed, the interior be well charred. The Chinese and Japanese use porce- lain tiles, in forming cisterns. This, we consider an excellent practice ; and one, which might be followed here, in the form of encaustic tiles, or glazed earthen- ware. We' see no objection, for this purpose, to the use of glass cast in large, thick plates, such as those used so generally, now-a-days, over areas and for sky-
