164 BLEACHING. 



same effect in whitening it, as by exposing it to the 

 action of the air and light in the field. 



The new method of bleaching was quickly and 

 successfully introduced into the manufactories of 

 France ; and almost as soon into those of Great 

 Britain. It is now universally adopted. The 

 advantages are, that the time required for bleach- 

 ing is shortened in a surprising degree so that 

 manufacturers experience a much quicker return of 

 their capitals ; and that it may be carried on at all 

 seasons of the year. 



The first way in which the oxymuriatic acid was 

 applied in bleaching was in the liquid state ; that is, 

 when water is impregnated with the gas. The 

 goods were immersed in this liquid according to 

 the nature of the objects to be bleached. Skeins 

 of thread were suspended on frames in the tub in- 

 tended to receive them ; cloth was rolled upon 

 reels. When every thing was thus disposed, the 

 tubs were filled with oxygenated muriatic acid, by 

 introducing a funnel that descended to the bottom 

 of the tub in order to prevent the dispersion of the 

 gas. The cloth, or thread, was made to pass 

 through the liquid by turning the frames, until it 

 was judged that the acid was exhausted by acting 

 on the colouring matter. 



But the volatility of this acid, and the suffocating 

 nature of its vapours, which produced extremely 

 noxious effects upon the health of the workmen, 

 rendered its use very difficult, although very in- 

 genious apparatus had been invented both by Ber- 

 thollet and by Mr. Watts. It was also found diffi- 

 cult to cause the acid to act upon all parts of the 

 cloths equally, when they were stratified in the cis- 

 terns with the acid. 



A considerable improvement was made in the 



