GNEISS 



685 



Glycerine has many important uses in the arts. The use of it as a soap, glycerine 

 soap, is now familiar to all. It may be used for preserving articles of food, especially 

 such as require to be kept moist, as fruits and the like, in tin cases. Meat is said to 

 keep well in glycerine, and preserve its flavour. It is recommended to modellers for 

 keeping their clay moist. In the Technologist, January 1858, a process of madder- 

 dyeing with the aid of glycerine is described. It has been much used in printing 

 processes, especially, for printing receipt and postage stamps. Vasseurs and Houbigant 

 patented an application of glycerine. They dilute it with four or five times its weight 

 of water ; with this, paper is moistened, and it retains its moist condition for any 

 length of time. It may be introduced into the paper pulp, or it may be mixed with 

 the ink. In either case copies can be readily taken by pressure. Glycerine never 

 freezes ; it is therefore recommended as a lubricant for delicate machinery, and it 

 has been used for floating ships' compasses, as it will not solidify in cold climates, or 

 evaporate in hot ones. 



Amongst other purposes to which glycerine has been applied, it has been substi- 

 tuted for lard, as a basis for ointments, by forming a plasma' of glycerine and starch. 

 Fifty grains of the Totcs-les-mois starch are to be rubbed with one ounce of glycerine,' 

 and the mixture heated to 240 for a few minutes, or till it becomes translucent. See 

 Watts's ' Dictionary of Chemistry.' 



Klever has estimated the solubilities of a number of substances in glycerine. The 

 following are his results: At the ordinary temperature 100 parts of glycerine 

 dissolve 



98 parts of Carbonate of soda. 



16 parts of Lactate of protoxide of iron. 



15 Oxalic acid. 



10 Acetate of copper. 



10 Benzoic acid. 



10 ,, Boracic acid. 



10 Chloride of barium. 



8 Bicarbonate of soda. 



8 Tartrate of iron. 



7*5 Bichloride of mercury. 



6'7 ,, Sulphate of cinchonine. 



5'5 Tartar emetic. 



5 Polysulphuret of calcium. 



4 Nitrate of strychnine. 



3 '5 Chlorate of potash. 



3 Atropine. 



2-25 Brucine. 



1-90 Iodine. 



1 Veratrine. 



0'50 Cinchonine. 



0-50 Quinine. 



0-45 Morphine. 



0-25 Tannate of quinine. 



0-25 Strychnine. 



0-20 Phosphorus. 



0-10 Sulphur. 



WITRO. See NlTRO-GLYCEBINE. 



GXiYOXXXiXXQTXi. See EXPLOSIVE AGENTS. 



GIiYPHOGRAPHY. A process introduced some years since to cheapen wood- 

 engraving. A metal plate was covered with a thick etching -ground, and an etching 

 made through to the metal in the usual manner. Several coats of ink were then 

 applied by means of a small composition roller. This adheres only to the varnish. 

 When the hollows are deep enough, the plate is placed in connection with a voltaic 

 battery, and copper is deposited in the usual way ; the result being a plate with the 

 drawing in relief. See ELECTRO-METALLURGY. 



GNEISS may be called stratified, or, by those who object to that term, foliated 

 granite, being formed of the same materials as granite, namely, felspar, quartz, and 

 mica. Lyell. 



Gneiss might indeed, in its purest and most typical form, be termed schistose 

 granite, consisting, ^like granite, of felspar, quartz, and mica ; but having those 

 minerals arranged in layers or plates, rather than in a confused aggregation of 

 crystals. Jukes. 



In whatever state of aggregation the particles of gneiss may have been originally 

 deposited, we know now that it is a hard, tough, prystaUine. rock, exhibiting curved. 



60 



50 



50 



50 



50 



50 



40 



40 



40 



35 



33 



33 



30 



27 



25 



25 



22-5 



20 



20 



20 



20 



20 



20 



20 



Borate of soda. 

 Arseniate of potash. 

 Arseniate of soda. 

 Chloride of zinc. 

 Tannin. 

 Urea. 

 Alum. 



Iodide of potassium. 

 Iodide of zinc. 

 Sulphate of zinc. 

 Sulphate of atropine. 

 Cyanide of potassium. 

 Sulphate of copper. 

 Cyanide of mercury. 

 Bromide of potassium. 

 Protosulphate of iron. 

 Sulphate of strychnine. 

 Acetate of morphine. 

 Acetate of lead. 

 Arsenious acid. 

 Carbonate of ammonia. 

 Chlorate of soda. 

 Hydrochlorate of ammonia. 

 Hydrochlorate of morphia. 



