SUGAR

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SUGAR. This important substance is a constituent part of a number of plants, It is afforded especially by the sugarcane, the maple, and the beet, When the cane is ripe, it is cut down, and crushed between iron cylinders, moved by the steamengine, water, or animal strength. The juice is received in a shallow trough, placed beneath the cylinders; whence it is conveyed into boilers, where it is heated with lime, care being taken to remove the scum as it rises. After having undergone considerable evaporation, it is called syrup, and is poured into a vessel called the cooler, where it is agitated with wooden stirrers, which break the crust as it forms on the surface. It is afterwards poured into casks, to accelerate its cooling; and, while it is still warm, it is conveyed into barrels, standing upright over a cistern, and pierced through their bottom with several holes, stopped with cane. The syrup, which is not condensed, filters through these canes, into the cistern beneath, and leaves the sugar in the state called Muscovado. This sugar is yellow, and is further purified by various processes, as that of boiling with bullock's blood, or with animal charcoal (bone black): and the passing of the syrup through a system of canvass filters, aided by the intermixture with it of a small quantity of pasty, gypsum and alumina, made by saturating a solution of alum with quicklime. Loaf sugar is procured by putting the SUGAR, after it has been thus purified, into ungiaz ed, earthen, conicalshaped vessels, having a hole at the apex, but placed in an inverted position : the base, after the sugai is poured in, is covered with clay. When thus drained of its impurities, it is taKen out of the mould, wrapped in paper, and dried or baked, in an oven. It is now loaf SUGAR, and, according to the number of processes: which it undergoes, is called single or double refined. Sugar candy is formed by dissolving loaf sugar in water, over a fire, boiling it to a syrup, and then exposing it to crystallize in a cool place. This is much esteemed in the East. The syrups which cease to afford sugar are sold by the name of molasses. The manufacture of sugar from the beet, which has now become so extensive in France, is a more complicated process. The beet roots are pulled out of the ground, and their necks and rootlets cut off. They are then washed, reduced to a pulp by a rasping machine, and pressed to obtain their juice, which scarcely differs from that of the cane, except in being somewhat less rich in sugar. The juice is transferred to a copper boiler, furnished with two stopcocks, the one of which is fixed near the bottom, and the other a few inches higher up, being previously mixed with one four hundreth part of sulphuric acid and a quantity of cream of lime, rather more than enough for the saturation of the acid. Heat is now applied as briskly as possible to the copper. A solid, thick froth, of a greenishgray color, forms, and deposits to a considerable amount, and the juice assumes a yellow hue, and becomes clarified. After an hour or two, the scum is removed, and thrown on drainers, to save as much of the juice as possible. The clear juice is now run off successively, by the two stopcocks, beginning with the higher, and the sediment is added to the froth on the filters. The mice is next transferred to a boiler, built on a level below the first, and is there evaporated by a quick fire. Whenever .ts density reaches to 1.12 (24° of Twaddel's hydrometer), animal charcoal is introduced in powder, and the concentration carried on, till its specific gravity is 1.24 (48° of Twaddel). The froth is removed as it forms. About two parts of animal charcoal are usually added to 100 of juice. The syrup is now filtered through woollen cloth, and allowed to cool. In the course of the night, a considerable quantity of sulphate of lime is deposited, which must be carefully separated, prior to boiling up the liquor for crystallization. This concluding stage of the process is the same as that employed for the juice of the sugarcane. The refining of the raw beet sugar is conducted in the same way as that of the cane, and the results are described as being equally productive. The extraction of sugar from the juice of the maple is exceedingly simple. At the commencement of the spring, in the Northern States and Canada, the sugar maple trees are tapped near the ground, by numerous apertures, and the sap is collected in wooden troughs ; two hundred pounds of which afford, by evaporation, fifteen pounds of a brownish SUGAR, which is capable of being refined in the same manner as the sugar from the cane and the beet. Pure sugar occurs as a white granular solid, but may be crystallized in four or sixsided prisms, terminated by twosided, or sometimes by threesided summits. Its specific gravity is 1.4' to 1.6'. The crystals are nearly anhydrous. When exposed to heat, sugar swells up, is decomposed with a peculiar smell, and finally bursts into flames at a temperature somewhat below ignition. When dissolved in one third its weight of water, it forms a syrup, which keeps well in close vessels; but if considerably diluted with water, it rapidly changes, particularly with contact of air, becoming sour and mouldy. Sugar is hardly soluble in pure alcohol, though proof spirit dissolves it in considerable quantity. Syrups, which have been rendered uncrystallizable, bitter and astringent, by combination with lime, barytes and strontites, resume their original properties, when these bases are separated by the equivalent quantity of sulphuric acid. The same holds true with regard to potash and soda. When quicklime is left for several months in combination with syrup, carbonate of lime is deposited in very acute rhomboids, and the sugar is converted into a mucilaginous jelly, of the consistence of paste. Several other oxides, and especially that of lead, have the power of combining with sugar. Thus, when ground litharge is heated with sugar and water, it is dissolved ; but after a while the liquor becomes opaque, and lets fall a white, insipid, light powder, insoluble in even a great quantity of boiling water, and which is a compound, in its dried state, of 100 of sugar, and 139.6 of oxide of lead. This saccharate of lead is decomposed by the feeblest acids, which seize the lead. Subace tate of lead does not precipitate sugar from its solution; and as this salt throws down almost every other vegetable and animal substance, it may be employed to separate sugar from other matters. Sugar has no action on salts, except at an elevated temperature. With the aid of water, it then reduces muriate of gold, the nitrates of mercury, and silver, the sulphate of copper, and reduces to the lowest term of oxidation several other salts. Sugar has been analyzed by several chemists. results : The following is a general view of theG. Lussac and Thenard. )xygen, 50.63 Carbon, 42.4? iydrogen, 6.90 Berzelius. 49.856 43.265 6.879 100.00 100.00 Prout, 53.35 39.99 6.06 100.00 lire 50.33 43.38 6.29 100.00M. Braconnot has recently extended our views concerning the artificial production of sugar and gum. Sulphuric acid (specific gravity 1.827) mixed with well dried elm dust, became very hot, and on being diluted with water, and neutralized with chalk, afforded a, liquor which became gummy on evaporation. Shreds of linen triturated in a glass mortar, with sulphuric acid, yield a similar gum. Nitric acid has a similar power. If the gummy matter from linen be boiled for some time with dilute sulphuric acid, we obtain a erystallizable sugar, and an acid, which M. Braconnot calls the vegetosulphuric acid. The conversion of wood, also, into sugar, will no doubt appear remarkable ; and when persons not familiar with chemistry, are told that a pound of rags can be converted into more than a pound of sugar, they may be disposed to consider the statement as a piece of pleasantry, though nothing can be more true.