INFLAMMABLES. 317 



8. USES, INT BLEACHING, and for other purposes* 



Jz.) It bleaches straw, woolen and silk y and gives silk lustre* 

 ulphur is burned in a barrel, in family operations ; the articles 

 to be bleached are hung up in the barrel, and moistened with water or 

 solution of pearlashes.f It also discharges iron moulds and vegeta- 

 ble stains from linen. For this purpose, the places must be made 

 thoroughly damp, and then two or three sulphur matches must be 

 burned close to them ; liquid sulphurous acid will thus be formed, 

 and the spots will soon disappear. 



(b.) A similar process is practised on a large scale in the arts ; 

 the sulphur is burned in chambers lined with sheet lead, and the 

 moistened articles are hung upon frames. J 



(c.) Prepared of a proper strength for liquid bleaching, by dis- 

 tilling in a glass retort 1 Ib. of wood shavings, with the same weight 

 of sulphuric acid, and placing two gallons of water in the receiver ; 

 if to be used to stop the fermentation of wine, only two quarts of 

 water are placed in the receiver. 



(d.) A rag, imbued with sulphur, is sometimes burned in cider 

 casks to preserve the cider from too rapid fermentation. 



(e.) The fumes of burning sulphur, (or in other words, sulphurous 

 acid gas,) were employed 1600 years ago in bleaching wool; but 

 the gas whitens only the surface, and therefore the liquid acid is pre- 

 ferred. 



(/.) Thenard says that the sulphurous acid is beginning to be 

 used to cure diseases of the skin that there are in various hospit- 

 als in Paris, baths of this kind that a few applications suffice to 

 remove psora, and that the tetters yield to the continued use of 

 this remedy. It is said that Dr. Gules, of Paris appliesj| the vapor 

 of burning sulphur mixed with air, to the surface of the body, as an 

 air bath, with much advantage in many chronic diseases of the joints, 

 the glands, and the lymphatics. Ure. 



******* 



Dr. Torrey informs me that he has made the liquid sulphurous 

 acid before his class, and that tubes of it may be sealed by the blow- 

 pipe, while immersed, (except the capillary extremity,) in a freezing 

 mixture. 



The hypo- or sub-sulphurous, and the hypo- or sub-sulphuric acids 

 will be mentioned after the sulphates and sulphites* 



* Sec Parkes on Bleaching. Essays, Vol. II, p. 337. 



t Water would probably be better, as the alkali would neutralize a part of the- 

 acid gas, and withdraw it from action. 



I Verbal communication to the author while in England, from a manufacturer. 



Fifth Ed. VII, p. 195. 



fl In an apparatus called Boite Fumigatoire. 



