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 a reputation in gouty affections have been found to contain lithium.

The first use of carbonate of magnesia medicinally was in the form of a secret medicine which must have acquired much popularity in the beginning of the eighteenth century. It was prepared, says Bergmann, by a regular canon at Rome, sold under the title of the powder of the Count of Palma, and credited with almost universal virtues. The method of preparation was rigidly concealed, but it evidently attracted the attention of chemists and physicians, for it appears that in 1707 Valentini published a process by which a similar product could be obtained from the mother liquor of "nitre" (soda) by calcination. In 1709 Slevogt obtained a powder exactly resembling it by precipitating magnesia from a solution of the sulphate by potash. Lancisi reported on it in 1717, and in 1722 Hoffmann went near to explaining the distinction between the several earthy salts, which in his time were all regarded as calcareous.

Hoffmann's process to obtain the powder was to add a solution of carbonate of potash to the mother liquor from which rough nitre had been obtained (solution of chloride of magnesium), and collect the precipitate. This being yielded by two clear solutions gave to the carbonate of magnesia precipitated the name of Miraculum Chemicum.

Magnesia was the name of a district in Thessaly, and of two cities in Asia Minor. The Greek "magnesia lithos," magnesian stone, has been frequently applied to the lodestone, but this can hardly have been correct, as the magnesian stone was described as white and shining like silver. Liddell and Scott think talc was more