Note 15 — BOOK VII.

Argol (Feces vini siccae,—"Dried lees of wine." Germ. trans. gives die wein heffen, although the usual German term of the period was weinstein). The lees of wine were the crude tartar or argols of commerce and modern assayers. The argols of white wine are white, while they are red from red wine. The white argol which Agricola so often specifies would have no special excellence, unless it may be that it is less easily adulterated. Agricola (De Nat. Fos., p. 344) uses the expression "Fex vini sicca called tartarum"—one of the earliest appearances of the latter term in this connection. The use of argol is very old, for Dioscorides (1st Century A.D.) not only describes argol, but also its reduction to impure potash. He says (V, 90): "The lees (tryx) are to be selected from old Italian wine; if not, from other similar wine. Lees of vinegar are much stronger. They are carefully dried and then burnt. There are some who burn them in a new earthen pot on a large fire until they are thoroughly incinerated. Others place a quantity of the lees on live coals and pursue the same method. The test as to whether it is completely burned, is that it becomes white or blue, and seems to burn the tongue when touched. The method of burning lees of vinegar is the same.... It should be used fresh, as it quickly grows stale; it should be placed in a vessel in a secluded place." Pliny (XXIII, 31) says: "Following these, come the lees of these various liquids. The lees of wine (vini faecibus) are so powerful as to be fatal to persons on descending into the vats. The test for this is to let down a lamp, which, if extinguished, indicates the peril.... Their virtues are greatly increased by the action of fire." Matthioli, commenting on this passage from Dioscorides in 1565, makes the following remark (p. 1375): "The precipitate of the wine which settles in the casks of the winery forms stone-like crusts, and is called by the works-people by the name tartarum." It will be seen above that these lees were rendered stronger by the action of fire, in which case the tartar was reduced to potassium carbonate. The weinstein of the old German metallurgists was often the material lixiviated from the incinerated tartar.

Dried lees of vinegar (siccae feces aceti; Interpretatio, die heffe des essigs). This would also be crude tartar. Pliny (XXIII, 32) says: "The lees of vinegar (faex aceti); owing to the more acrid material are more aggravating in their effects.... When combined with melanthium it heals the bites of dogs and crocodiles."