Examination of water (chemical and bacteriological) / by William P. Mason.

  • Mason, William Pitt, 1853-1937.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Examination of water (chemical and bacteriological) / by William P. Mason. Source: Wellcome Collection.

    24/170 (page 12)
    Water-analysis cannot be properly conducted in a general laboratory, because many of the tests would be ruined by the fumes common to such a locality. A separate room, reserved exclusively for water-work, is the best arrangement. The author finds it con- venient to have the woodwork therein painted white and to have a broad titration shelf fixed across the window, with a black curtain capable of being pulled down to the level of the titration-dish. Excellent con- ditions are thus given for noting slight differences in colors. The appearance and turbidity of a water is best de- termined by using a brass tube 2\ inches in diameter and 2 feet long, closed at the ends by disks of quarter- inch plate glass held in place by screw-caps (Fig. i).* Such tubes are easily cleaned and give excel- lent satisfaction. For the purpose of measuring the amount of turbidity, a standard is prepared, consist- ing of one gramme of exceedingly fine kaolin (ob- tained by elutriation) suspended in one litre of dis- tilled water. Each c.c. of this preparation will con- tain one milligramme of suspended clay. Having nearly filled the duplicate observation-tube with distilled water, enough of the clay standard * Such tubes may be obtained from Richards & Co., No. 30 East T8th Street, New York City.