Water Analysis.
—In order to be assured as to the quality of drinking water, it should be subjected to analysis and the result of the analysis inspected by a physician of good standing. Such analysis may usually be obtained free of charge from the State Board of Health and if asked, the Chief Chemist will usually give his opinion regarding the quality as drinking water.
In chemical water analysis, the total amount of solids, regardless of their nature is taken as indicative of its excellence for drinking purposes. These solids may be either in suspension and give the water a color or produce a turbidity, or they may be entirely in solution and the water appear colorless. English authorities on the subject place the allowable proportion of solids at 500 parts to the million. Any water that contains more than 500 parts to the million is condemned for drinking purposes. Water containing 500 parts or less to the million is considered good. The Standard of the American Board of Health permits the use of water for city supply that contains 1000 parts of solid matter to the million.
The amount of solids contained in water is not at all a definite indication of its quality for drinking purposes, as may be inferred from the widely varying amounts permitted by the different authorities, but it gives an indication of its character because of the known physiological action of the contained solids.
Chemical analysis alone cannot be taken as a complete indication of the character of water, because such analysis shows nothing of the bacteria that may be present. The organic matter may indicate the possible presence of bacteria, but microscopic examination will be required to determine its harmful properties.
As examples of the chemical constituents of potable waters, the following furnish illustrations of different types of water in general use.