“PURE” WATER.

“PURE” WATER.

Apropos of the story which recently appeared in these columns of the decomposing body of an alligator being found in a water main, a correspondent of a London contemporary quotes the case of a “servant girl from the country who, on being asked her reason for wishing to leave a good situation in London, replied that she could not abide the London water—there was neither taste nor smell in it.” It also recalls to his mind a case which came tinder bis notice some years ago. “I was in the water supply department of a firm of engineers (he writes). We were called in to advise on the supply to a country house, the water for which was drawn from a well nearly 303 feet deep in the chalk, and which ought therefore to have been quite pure. On analysis, however, it proved to be badly contaminated with organic matter. The well was cleaned out, on my advice, and about ten feet of filth, including a large quantity of bones, was removed. I remarked that no doubt the hones came from some animal that had fallen down, and was told, ‘Oh, yes. some years ago there was a pig and a sheep that we know of fell down; but. as the well was rather deep, the tenant didn’t trouble to get them up,’ and evidently went on drinking the water!’”

Pure Water.

0

Pure Water.

Until recently the purest water that has been physically examined was that obtained by Professor F. Kohlrausch by distillation in vacuo, and which showed an electricconductivity only one-third that of water distilled under atmospheric contact. Some low conductivity only endured for a short time, owing to the water taking up foreign matter from the sides of the containing vessel or the electrodes. The distilling apparatus used on that occasion, after standing full of water for nearly ten years, has lately been used by Messrs. Kohlrausch and A. Heydweiller in some new experiments which have been described in the “ Transactions” of the Academy of Science at Berlin. The water obtained has, when tested at 18 degrees C., only one-sixth of the conductivity of thefornur sample; the resistance of one square millimetre at the freezing point being the same as that of a copper conductor of the same section, 25,000,000 miles long, or more than r.ooo times the circumference of the earth. The foreign matter contained in this water only amounts to a few thousandths of a milligramme in the litre.—Progressive Age.