758. To detect the Mixture of Arsenic.—A solution of blue vitriol dropped into any liquid in which arsenic has been put, will turn it green.
759. To test Mushrooms.—Rub the upper skin with a gold ring or any piece of gold: the part rubbed will turn yellow if it is a poisonous fungus.
760. To prepare Salt.—Set a lump of salt in a plate before the fire, and when dry, pound it in a mortar, or rub two pieces of salt together; it will then be free from lumps, and in very fine powder.
761. To make Cheap and Good Vinegar.—To eight gallons of clear rain water, add three quarts of molasses; turn the mixture into a clean tight cask, shake it well two or three times, and add three spoonsful of good yeast, or two yeast cakes. Place the cask in a warm place, and in ten or fifteen days, add a sheet of common wrapping-paper, smeared with molasses, and torn into narrow strips, and you will have good vinegar. The paper is necessary to form the "mother," or life of the liquor.