GLYCOLS. 141 



ether, and at the end of the reaction the mass diluted 

 with four times its volume of water and then boiled 

 for a few hours. By neutralizing the liquid with 

 barium carbonate, the soluble barium salt is prepared. 

 Is also formed by mixing barium ethylsulphate with 

 sulphuric anhydride, evaporating the excess of the 

 anhydride and boiling for a long time with water. 

 The sodium salt is formed by direct union of ethylene 

 oxide with sodium bisulphite, and by treating ethylene 

 chlorhydrine with a concentrated solution of sodium 

 sulphite. The free acid can be evaporated to a syrup ; 

 decomposes, however, when further evaporated. Mono- 

 basic acid. Its salts crystallize well and are very 

 stable. The potassium salt, when distilled with phos- 

 phorus chloride, yields isethion chloride (chlorethyl sul- 

 pho-chloride) CH'OLCH'.SCPCl, a liquid, boiling at 

 200, which when heated with water is decomposed 

 into chlorcthylsulphurous acid CH 2 C1.CH 2 .S0 2 .OH and 

 water. 



Taurin (Amidoisethionic acid), C 2 H 7 TS0 3 = 



H 2 

 OH 2 SO 2 OH Occurs free and in combination with 



cholic acid, as taurocholic acid, in the animal organism, 

 in bile, in the contents of the alimentary canal, in the 

 lung tissue, in the kidneys. Can be best prepared by 

 evaporating bile to which has been added hydrochloric 

 acid, removing the resinous substance which is thrown 

 down, and mechanically separating the crystals of 

 taurin and sodium chloride, which make their appear- 

 ance on cooling. Is produced artificially by heating 

 ammonium isethionate to 210, and by heating silver 

 chlorethylsulphite with aqueous ammonia to 100. 

 Large, clear crystals, easily soluble in hot water, but 

 slightly in cold water, insoluble in alcohol. It fuses, 

 and decomposes at ' a high temperature. It does not 

 yield well characterized compounds with bases nor 

 with acids. 



2 OTT 

 Disulphetholic acid, C 2 H 6 S 2 6 = 2 SO 2 OH is 



