Page:Chronicles of pharmacy (Volume 1).djvu/362

 It should be mentioned that it was by the examination of Epsom salts that Black was led to his epoch-making discovery of the distinction between the alkaline earths, and also of fixed air, in 1754.

In Quincy's "Dispensatory" (1724), medicinal waters like those of Epsom are described as Aquæ Aluminosæ. It is stated that there are many in England, scarce a county without them. The principal ones about London are at Epsom, Acton, Dulwich, and North-hall. They all "abound with a salt of an aluminous and nitrous nature," and "greatly deterge the stomach and bowels." But it is easy to take them too frequently, so that "the salts will too much get into the blood, which by their grossness will gradually be collected in the capillaries and glands to obstruct them and occasion fevers." After some more advice Quincy adds—

"It is difficult to pass this article without setting a mark upon that abominable cheat which is now sold by the name of Epsom waters. Dr. Grew, who was a most worthy physician and an industrious experimenter, made trial how much salt these waters would leave upon evaporation, and found that a gallon left about two drams, or near, according to my best remembrance, for I have not his writings by me. He likewise found the salt thus procured answered the virtues of the water in its cathartic qualities. Of this an account was given before the Royal Society in a Latin dissertation. But the avaricious craft of a certain furnace-philosopher could not let this useful discovery in natural knowledge rest under the improvement and proper use of persons of integrity; but he pretended to make a great quantity for sale; and to recommend his salt translated the Doctor's Lecture into English to give away as a quack-bill."

Quincy proceeds to tell us how other competitors came in, and how the price was so reduced that what was first sold at one shilling an ounce, and could not honestly be made under (Quincy apparently refers to the salt made by evaporation), came down in a short time to thirty shillings per hundredweight.