346 OLEIC AND BORIC ACIDS 



OLBIC ACID, CH 3 (CH 2 ) 7 CH : CH(CH 2 ) 7 COOH. 



Acid um oleicum, or hydrogen oleate, is obtained by the 

 saponifying action of alkalies and subsequent action of acids, 

 or by the action of superheated steam upon the olein of fats. 

 Usually not quite pure (B.P.). It is a straw-coloured liquid, 

 occasionally with a faintly rancid smell, and a slight acid 

 reaction. Becomes brown and more acid on exposure to the 

 air. Insoluble in water ; readily soluble in alcohol (90 per 

 cent.), chloroform, or ether. Specific gravity, - 890 to 

 0*910. Oleic acid is used in pharmacy for dissolving various 

 metallic oxides and the alkaloids morphine, aconitine, 

 atropine, veratrine, and cocaine. It is used in the prepara- 

 tion of mercuric oleate and of various ointments. (Squire.) 



BORIC ACID 



ACIDUM BORICUM. Hydrogen Borate. Boracic Acid. 

 H 3 B0 3 . 



Boric acid is obtained from borax by the action of sul- 

 phuric acid. In volcanic regions in Italy and in the Lipari 

 Islands, through natural fissures or holes bored in the earth, 

 there issue vapours and jets of steam, which are passed 

 through water, and the solution, subsequently evaporated, 

 yields colourless, pearly, lamellar crystals of boric acid. 

 They are feebly acid, and bitter, with a sweetish after-taste, 

 and dissolve in thirty parts of cold water, in three of boiling 

 water, in sixteen of rectified spirit, and five of glycerin, and 

 communicate a green colour to an alcoholic flame. The 

 addition of borax increases the solubility of boracic acid. 

 Aiding the fusion of other bodies, it is much used as a blow- 

 pipe test : mixed with seven parts of acid potassium 

 tartrate, it constitutes the soluble cream of tartar of the 

 shops. When heated, three molecules of water are driven 

 off, and anhydrous vitreous boric acid remains (B 2 3 ). 



ACTIONS AND USES. Boric acid is a non-volatile, non-irri- 

 tating but rather feeble antiseptic, which has more effect on 

 organised than on chemical ferments. Ingested, it is 

 readily absorbed by the digestive mucous membrane, and 



