Page:Transactions of the Provincial Medical and Surgical Association, volume 4.djvu/252

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The water of St. Ann's Well varies in its temperature from 47° to -9°. That of the Holy Well, as it falls from the spout in the pump-room, is about 49° or 49.5: being conducted from the source to the pump-room by a short pipe, it is more liable to be influenced by atmospheric changes than the water at Great Malvern.

The alcoholic solution of soap, muriate of barytes, nitrate of silver, and the other usual tests for the muriates and sulphates, produce hardly a perceptible change, and sometimes none at all, in either of these two waters. After a long period of dry weather, the nitrate of silver will cause a light whitish cloud of the muriate.

The great purity of the Malvern water may be inferred from the above test, and from the common remark that it never curdles soap; that it forms a clear solution with the subacetate of lead, and redissolves the earthy deposit so often formed in tea kettles which have been used to boil the usual hard spring waters in.

Forty fluid ounces, of the water from St. Ann's Well, were evaporated very slowly, to about three, in an open Wedge-wood-ware dish, and then transferred into a shallow glass vessel, being still clear and transparent. The whole of the fluid being slowly driven off, there remained a brownish film, which, when carefully scraped together, weighed very nearly one grain: it deliquesced after a short exposure to the air.

Thirty-two fluid ounces were, on another occasion, subjected in the same manner to slow evaporation, and the solid residue weighed three-fourths of a grain.

The solid contents, therefore, of a gallon of the pure Malvern water do not amount to more than three grains. Various other experiments and evaporation's (detailed in the Dissertation on the Malvern Waters, second edition, p. 217)