Page:Collier's New Encyclopedia v. 04.djvu/401

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GLUCOSURIA 337 GLYCERAMIC ACID parts of water, and cooled with ice; then six parts of powdered calcium hydrate are added, the calcium compound of levulose is precipitated and separated from the soluble calcium compound of dextrose by strong pressure, washed, and decomposed by carbonic-acid gas. The term "glucose" is generally applied to a mixture composed of dextro-glucose, mal- tose, dextrin and water prepared from corn starch, by heating with dilute acids. It is widely used in the manufacture of candy, and was formerly an important commodity in the brewing of malt liquors. GLUCOSimiA, a form of diabetes. The name has reference to the fact that the urine of persons affected with this disease contains sugar. GLUE, an impure gelatine. It is pre- pared from the clippings of hides, hoofs, and horns. Good glue is semi-transpar- ent, and free from spots and clouds. When wanted for use, it is broken in pieces and steeped in cold water till it softens and swells. It is then melted over a gentle fire, or, what is better, in a water bath, and applied in a liquid state with a brush. Marine glue is a composition used for cementing materials that are exposed to moisture. It is made by dissolving 1 part of india-rubber in 12 parts of mineral naphtha, and adding 20 parts of powdered shellac. It not only resists wet, but cements glass and metals as well as wood. White fish-glue, or diamond cement, is made of isinglass dis- solved in alcohol. GLUME, or GLUMA, the exterior series of scales constituting the flower of a grass. It consists of empty bracts. The name was given by Linnaeus and adopted by Lindley. GLUMELLA, a name given by De Candolle and Desvaux to two bracts with- in the glumes of a grass; the other name being pale. In one of the bracts the midrib quits the blade a little below the apex, and is elongated into an awn, arista, or beard, while the other bract which faces the fruit has its back to the rachis, is bifid at the apex, has no dorsal veins, and has a rib on each side of its inflexed edges. These two bracts are called by Linnaeus the corolla of the grass, by Jussieu the calyx, by Robert Brown the perianth, and by Lindley and others its paleae. GLUTAMIC ACID, an acid obtained by boiling vegetable gluten with dilute sulphuric acid, or casein with hydro- chloric acid and stannous chloride. GLUTEN, an albuminous substance, obtained by mixing 10 parts of wheat- meal with 8 parts of water, and allowing it to stand for half an hour; it is then washed with water, and kneaded, till all the starch is washed away, and the gluten thus obtained is a tenacious, yellowish- gray, elastic mass, which dries into a horny, semi-transparent mass, resem- bling glue. GLUTEUS, or GLUTEUS, three muscles of the hip, the G. maxirmis, the G. medius, and the G. minimus. The first is a very large and coarsely fasci- culated muscle, which makes the buttock prominent in man; its use is to extend the thigh. The second is smaller; it is partly covered by the muscle already mentioned, and acts when one stands. The third is the smallest; it is covered by the second one, and acts as an abduc- tor of the thigh. GLUTIN, or GLUTINE, vegetable gelatine. It is obtained along with mucin by heating gluten in small fragments, with alcohol of 80 per cent., and then with alcohol of 70 per cent. ; the alcoholic solutions are united, and the half of the alcohol distilled off. On cooling it deposits a mixture of glutin and mucin. The de- posit is dissolved in 50 per cent, alcohol, and filtered through calico while hot, and then agitated till it is cold; most of the mucin is precipitated, the filtered liquid is evaporated in a water bath, and the glutin dissolved in alcohol. GLUTTON, in zoology, the popular name for the wolverine, a carnivorous mammal of the family Melidas (badgers). Its length is from two to three feet. It occurs in high latitudes in Europe, Asia, and North America. Its motions are slow, but it manages to feed on mice, marmots, and other rodents, and, when it can obtain them, on larger quadrupeds, alive or dead. Its fur is of little value. GLYCERALS, in chemistry, com- pounds analogous to acetals, obtained by heating glycerin with aldehydes for 30 hours at a temperature of 170° to 180°; as acetoglycerale, CbHjoOs. It boils at 184°. GLYCERAMIC ACID, in chemistry, serin. C,H,N03 or C H3(0H) -NH.CO • OH, a monobasic, triatomic, amido-acid, obtained by boiling silk with water and evaporating the filtered solution, adding a quarter of its volume of sulphuric acid, and boiling for 24 hours; then it is neu- tralized with excess of calcium hydrate, the filtrate is evaporated and a little H2S0< added to neutralize it. Tyrosin and calcium sulphate first separate out on evaporation, then serin, and lastly a little leucin. The serin is dissolved in 40 parts of cold water, filtered, the filtrate neu-