274 ■ INOEGANIC AGENTS 



Derivation.— ^atuval deposits of the crude article occur 

 as incrustations on shores of lakes in jSTevada and California^ 

 which are purified by calcination and crystallization. Borax 

 is also made by boiling boric acid with sodium carbonate. 

 4 HoB O3 + :N'a2C O3 = NaaB^O^ + C O2 + 6 Hg 0. 



Properties. — Colorless, transparent, monoclinic prisms,, 

 or a white powder, inodorous and having a sweetish, alka- 

 line taste. Slightly efiiorescent in warm, dry air. Soluble 

 in 16 parts of water at 59° F., and in 0.5 part of boiling 

 water; insoluble in alcohol. At 176° F. it is soluble in one 

 part of glycerin. Borax is slightly alkaline. 



ACTIOa" OF BOBIO ACID AND BOEAX. 



Boric acid and borax are essentially mild, non-irritating 

 antiseptics. These agents are practically harmless, as ordi- 

 narily employed, yet death in man has been reported from 

 absorption of a 5 per cent, solution of boric acid used for 

 irrigation of the large cavities of the body, and fatalities 

 have resulted from its external use and from the ingestion 

 of quantities of boric acid. 



Three drachms of boric acid may be given daily to dogs, 

 without causing any untoward effect. In man, boric acid 

 poisoning has been exhibited by feeble pulse, subnormal 

 temperature, vomiting, erythema and swelling of superficial 

 parts, muscular weakness, involuntary evacuations, coma, and 

 disordered respiration. Boric acid is eliminated by the urine, 

 sweat, saliva and fteces. Borax tends to alkalize the urine, 

 but neither borax nor boric acid are diuretics. 



Boric acid and borax, like other antiseptics, relieve 

 itching and destroy parasites upon the skin. Boric acid 

 exerts an antiseptic action upon the contents of the digestive 

 tract and upon the urine. It is thought to possess some 

 emmenagogue action. 



USES OF BORIC ACID AND BOEAX. 



The value of boric acid and borax is chiefly surgical. 

 They are employed more commonly upon the mucous mem- 



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