Fig. 122.—Hot-water supply with gas heater, connected to the range boiler.
Fig. 122 shows the heater connected with a range boiler. In this case the heater may be considered as taking the place of the water-back. It may, however, be used as an auxiliary heater. In the picture of the kitchen shown in Fig. 80, an instantaneous heater is shown attached to the range boiler. It is located in this case between the kitchen range and the boiler.
CHAPTER VII
WATER SUPPLY
The use of water enters into each detail of the affairs of everyday life and forms a part of every article of food; its quality has much to do with the health of the family, and its convenience of distribution lends greatly to the contentment of its members. The family water supply should be as carefully guarded as means will permit, and judicious care should be exercised to prevent the possibility of its pollution. Where the source of the water is known, it should be the subject of unremitting attention.
Water comes originally from rain or snow and as it falls, it is pure. Water, however, in falling through the air absorbs the contained vapors and washes the air free from suspended organic matter in the form of dust, so that when it reaches the earth rain water contains some impurities.
As the water is absorbed by the earth, it comes into contact with the mineral matter and organic materials of animal and vegetable origin contained in the soil; and as water is a most wonderful solvent, it soon contains mineral salts and possibly the leachings from the organic substances through which it passes. The impurities usually found in well water are in the form of mineral salts that have been taken up from the earth, but other contaminating materials may come from the surface and be carried into the well by accidental drainage.
Water that is colorless and odorless is usually considered good for drinking and in the absence of more accurate means of determination may be used as a test of excellence; but it often happens that water possessing these qualities is so heavily freighted with mineral salts as to be the direct cause of impaired health. Again, water that appears pure may be polluted with disease-producing bacteria to such an extent as to endanger the lives of all who use it. The fact that a source of drinking water bears a local reputation for purity, because of long usage, cannot be taken as a test of its actual purity until it has been subjected to chemical and bacterial examination.
It must not be inferred that all water is likely to be unsuitable for drinking; there is, however, a possibility of the water being polluted from natural sources and from accidental causes, that are sometimes preventable; and the only means of determining the purity of water is by chemical and bacterial examining.