884 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



called cryolite. Its principal locality is at Arkseidforcl, West 

 Greenland. According to analysis it contains of 54.2 per cent of 

 flnorine, 32.9 per cent of sodium, and 12.9 per cent of aluminum. 

 Finding that in Denmark it was even used by itself in the manu- 

 facture of soap, the company resolved to secure one of their num- 

 ber to the locality, and, if possible, to secure the monopoly for the 

 United States from the Danish government. The mission was 

 quite successful. A Danish company, under the government 

 charge, has entered into contract with the American company by 

 which the latter agreed to remove, at its own expense and in its 

 owm vessels, not less than 6,000 tons annually, and for which a 

 certain price has to be paid, according to analysis by a chemist 

 who has been sent here in the interest of the Danish company, for 

 the cryolite as dug out is not quite free from other mineral sub- 

 stances. Prof. Shephard has lately described three or four mineral 

 substances which were lately discovered in the cryolite. On my 

 visit to the soda works I saw several piles of cryolite containing 

 not less than 8 or 10,000 tons, brought to our shores in about 

 twenty schooners. 



Professor Julius Thomson, of Copenhagen, has established in 

 that city large Avorks for decomposing cryolite by a new patent 

 process, using the various lime compounds, such as chalk, caustic 

 lime, chloride of calcium, and, according to his method, seven 

 other establishments are operating in Germany. The United 

 States company is likew^ise benefited by this process. The supply 

 of cryolite in Greenland appears to be inexhaustible, and it has 

 been calculated that 100,000 tons deposit can be obtained without 

 enterinfif into the bowels of the earth. The formula of crvolite is 

 3 Na Fl-f-Alg Flo. Its hardiness is 2.5 and its specific gravity 

 2.94. It is fusible into a white enamel even in a candle flame; is 

 perfectly soluble in oil of vitriol, but not so in hydrochloric acid. 

 The object of using cryolite is to obtain from it the amount of the 

 metals which combine with oxygen to form oxides and salts, or, in 

 other words, when cryolite is completely decomposed it yields to 

 the 100 lbs. 24 lbs. of alumina and 44 lbs. of soda (anhydrous), or 

 76 lbs. of pure carbonate of soda, or 204 lbs. the common crystallized 

 sal-soda. The cryolite is decomposed and manufactured into soda 

 and sulphate of alumina by the following process, either in the 

 wet or dry way : If in the wet way, the finely ground cryolite is 

 boiled with slacked lime, whereby salts of soda and alumina are 

 formed, the insoluble part being a fluoride of calcium; 80 lbs. of 



