[602]. Litharge. The word is derived from λὶθος, Lapis, a stone, and ἄργυρος, Argentum, Silver; from the fact of the lead being thrown off in this state during its application for the refinement of Silver.
[603]. That the oak cask imparts astringent matter to the contained spirit, is shewn by the facts enumerated under the history of Brandy, see Spiritus Tenuior.
[604]. Sir George Baker considered the dry-belly-ache, which is common to drinkers of new Rum, in the West Indies, entirely referable to its contamination with Lead.
[605]. See next Note.
[606]. I uniformly adopt this plan; the acetic acid is the best guard that can be selected to protect the salt from decomposition; even the Tartrate of Lead, which is so insoluble in water, forms with vinegar a soluble triple salt.
[607]. Royal Preventive.—This pretended prophylactic against venereal virus is a solution of Acetate of Lead.
[608]. Peroxide of Potassium is produced by heating the metal in a considerable excess of oxygen. It is an orange-coloured body, which, upon being put into water effervesces, and gives off oxygen, and is thus reduced to the state of protoxide.
[609]. Potass forms the basis of many of those preparations, sold as Depilatories; in some instances combined with Lime. Colley’s Depilatory appears to consist of Quick-lime, and a portion of Sulphuret of Potass.
[610]. Sal Prunelle. Nitre, when coloured purple like a plum, has been long esteemed in Germany as a powerful medicine, under this name.
M. Chevreul supposes the urinous taste attributed to fixed alkaline bases not to belong to these substances, but to the ammonia, which is set at liberty by their action on the ammoniacal salts contained in the saliva; the proofs of which, he says, may be derived from the facts that the sensation disappears upon pressing the nostrils; and that the same odour is perceived when we smell to a mixture of recent saliva and fixed alkali, made in a small glass or porcelain capsule. (See my work on Medical Chemistry, § 8.)