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Nelson's Patent Gelatine

This is made from cuttings of the hides of cattle, and skins of calves. These, freed from hair, flesh, fat, &c., are washed and scoured, then macerated for 10 days in a lye of caustic soda, and afterwards placed in covered vessels at a liquid or substance for examination on a slip of common white glass, and to add to them a drop of the test liquid. By placing the glass over a sheet of white paper, the effect will be rendered more perceptible. ring to substances which hold a prominent A number of tests, not included here, referplace in some special process, have been introduced in immediate connection with the found in the index under the head of the artidescription of those substances, and will be cle to be tested.

Place a spoonful of ground coffee gently on 4373. Test for Chicory in Coffee. the surface of a glass of cold water. The pure coffee will float for some time, and brown tint as it falls. temperature of 60° to 70° Fahr. until they scarcely color the water; the chicory, if any become tender; then washed from the alkali, be present , rapidly absorbs the water and sinks exposed to the vapor of burning sulphur until to the bottom, communicating a deep reddishthey become sensibly acid, dissolved in earthen vessels heated to 150°, strained, put into settling settling vessels heated to 100° or 120° for nine hours, the clear liquor drawn off and poured on the cooling slabs to the depth of is pure, it will rise to the surface and hardly an inch. When cold, the jelly is cut in pieces, washed till free from acid, redissolved at 85°, poured on slabs, cut up, and dried on nets. placed in a small bottle of cold water, and Or a spoonful of ground coffee may be shaken for a moment; if the sample of coffee tinge the water, whilst if the coffee is adulterated with chicory, the latter will fall to the bottom and color the water as before. A duced, however, if the coffee be adulterated similar coloration of the water will be prowith burnt sugar, which is the basis of the socalled " coffee essences or extracts." 4374. Το Test Tea. Pure China tea is