TO ASCERTAIN THE PURITY OF WATER.

Te Aroha News, Volume VI, Issue 332, 9 January 1889, Page 6

TO ASCERTAIN THE PURITY OF WATER.

Un'ioutuxately, ib is no eapy point to tell whether Vvater is for the detection of e\en the coarsest* impurities is a matter demanding much skill from the chemist and ( he microscopist. Wholesome water should be colourless, odourless, and tasteless. Tt should send out air-bubbles when poured out from one vessel to another, and should form with soap a uniform opaline fluid ■which does not sepaiate after standing tor several hours. A drop of good water falling upon the finest and whitest cloth or papei ■will not leave the faintest stain behind. As a rough test for the purity of water may be mentioned the addition of a solution of permanganato of potash, better known as Condy's fluid. This fluid is of a beautiful purple colour, and when added to water tree from organic impurity, the colour remains, although, of coiuse, it is diluted. When, however, the water contains much organic impurity, the purple colour disappears, or is replaced by a brownish discolouration. Water which takes (he colour out of Conthft, Fluid in not safe to drink. Another simple test consists in tilling a clean pint bottle three-fourths full of %he water to be tested, and dissolving in the water half a teaspoonful of the purest sugar— -loaf or granulated will answer; cork the bottle, and place it in a warm place for two days. If in twenty-four or forty-eight hours the water becomes cloudy or milky it is unfit for domestic use. If it remains perfectly clear ib may safely be used. This test is more especially for sewer contamination — one of the worst forms of impurity of water, so far as the spread of disease by it is concerned.