GLYCERINE 



2516 



GNAT 



duced for every nine pounds of stearin; in the 

 latter, one pound of glycerine for about eleven 

 pounds of dry soap. The glycerine is purified 

 by distillation in superheated steam. About 

 100,000 tons is the world's annual production. 



Chemists prefer to call pure glycerine glyc- 

 erol; good commercial glycerine is over ninety- 

 nine per cent pure glycerol. At a low tem- 

 perature glycerol sometimes solidifies into 

 crystals, melting at 63 F., but this is rare, 

 and just what is necessary to start the crystal- 

 lization is not known. Ordinarily even the 

 purest glycerine remains liquid, however cold 

 it is kept. The boiling point, 552, is very high 

 for an organic compound. It is very hard to 

 set glycerine on fire. It burns with a colorless 

 flame without charring, and, if pure, leaves 

 no ash. At the ordinary temperature glycerine 

 does not evaporate. On the other hand, it 

 absorbs moisture from the air; it will take 

 up half its own weight of water in this way. 

 These properties make it a very useful sub- 

 stance to add to materials to prevent their 

 drying out. Among the commodities to which 

 it is added for this purpose are tobacco, copra 

 (shredded cocoanut), confectionery, heavily- 

 starched cotton goods, and inks for rubber 

 stamps. The tobacco industry of the United 

 States consumes about 2,500 tons of glycerine 

 a year. 



Glycerine mixes with water and alcohol in 

 all proportions and dissolves many inorganic 

 and organic substances. Some dyes are dis- 

 solved in glycerine and then mixed with water. 

 Stains made on linen by coffee and tea can 

 be removed by moistening the material with 

 glycerine, allowing it to stand for a time and 

 then steaming or washing with soapy hot water. 

 Glycerine added to water lowers its freezing 

 point. For this reason it is sometimes used 

 in gas meters, floating compasses and auto- 

 mobile radiators. Mixed with lead oxide it 

 makes a good cement. 



Glycerine feels oily and warm. The warmth 

 is due to the mixing of the glycerine with water, 

 which it extracts from the skin. It is used in 

 medicine to allay inflammation, thus having 

 a soothing effect. The same emollient property 

 makes it useful as a cosmetic for chapped 

 hands and sore lips. Taken internally in very 

 small doses it is harmless. Larger doses have 

 a purgative action and very large doses may 

 even prove fatal. It is sometimes used as a 

 solvent for other medicines. As a preserva- 

 tive, glycerine is sometimes applied to un- 

 tanned hides and to meat. 



The greatest industrial use of glycerine is 

 for the manufacture of the powerful explosive, 

 nitroglycerine (which see). See, also, ALCOHOL; 

 EXPLOSIVES; FAT; SOAP. 



GLYN, glin, ELINOR, an English novelist 

 whose works have been widely read and much 

 discussed because of their sensational char- 

 acter. Her early novels, of which the most 

 noteworthy were The Visits of Elizabeth and 

 The Reflections oj Ambrosine, attracted no 

 special attention, but Three Weeks, which ap- 

 peared in 1907, was one of the most talked-of 

 books of the decade. Later publications in- 

 clude Elizabeth Visits America, The Reason 

 Why and His Hour. Most of Mrs. Glyn's 

 works are unwholesome in tone, for they treat 

 of sex questions in a morbid, unpleasant man- 

 ner. 



Mrs. Glyn is by birth a Canadian, the daugh- 

 ter of Douglas Sutherland of Toronto. Clay- 

 ton Glyn, to whom she was married in 1892, is 

 an Englishman, but they have always preferred 

 to live in France. 



GLYPTODON, glip'tohdon, a gigantic ex- 

 tinct mammal, which was probably ten or 

 twelve feet in length. Its fossil remains have 

 been found in South America, and occasionally 

 in the United States. It had a solid armor of 



SKELETON OF THE GLYPTODON 



jointed -plates, arranged in transverse rows, and 

 the head and tail were covered with similar 

 plates. The character of its claws shows that 

 the animal could not have burrowed, like the 

 armadillo, although it is believed to have 

 belonged to the same family. 



GNAT, not, a name given various "blood- 

 thirsty," irritating insects, the most common 

 being the mosquito. All gnats are two-winged ; 

 each is equipped with a long, sharp, sucking 

 and piercing organ called a proboscis (which 

 means snout or trunk). Most gnats lay their 

 eggs on water, where they float three days 

 and then hatch. If standing pools of water 

 were removed, these irritating insects would be 

 less numerous. The buffalo gnat is very an- 

 noying to domestic animals. In the northern 

 woods an almost invisible gnat called the 

 punky is a most troublesome pest; it is so tiny 



