322 New Method of Bleaching 



the oxygenated muriatic acid, are to be employed after any 

 steaming, the goods should first be washed. 



When silk, sheep's wool, or goods containing sheep's wool. 

 Of animal hair or fur of any kind, are wished to be cleaned, 

 scoured or whitened by the above described method, the lye 

 employed ought to be much weaker than in the case of cot» 

 ton, flax, or hemp, or of goods manufactured of these or any 

 of them ; for a strong caustic lye would entirely destroy the 

 former, and convert them into a saponaceous matter. 



By the means above described, or by another or different 

 application of the volatile alkali or ammonia, the manner of 

 performing which shall be imuiediately described, a degree 

 of whiteness and purity may be given to cotton-wool, flax, 

 hemp, silk, and sheep's wool, and to goods of every descrip- 

 tion made or manufactured of any of them, or of mixtures of all 

 or any of them, which cannot otherwise be obtained but at 

 a much greater expense. 



When the volatile alkali is to be employed in place of that 

 already described, that as little of the volatile alkali as possible 

 may be lost, it is recommended, that instead of the safety- 

 valve being affixed to some part of the steaming-kettle or of 

 the steaming vat, or of the. tube of communication between 

 them, so as to allow the steam to escape when it acts with a 

 certain force, it may be attached in such a manner that 

 when opened by the internal pressure the vapour may not 

 escape into the atmosphere and be lost, which would occasion 

 a waste of the alkali, but may pass into a worm passing 

 through a refrigeratory, that it may be condensed, and fall 

 into a receiver adapted to the lower extremity of the worm. 

 This part of the apparatus is exactly similar to that employed 

 in the distillation of ardent spirits ; but the receiver should be 

 surrounded with cold water as well as the worm, the more 

 effectually to condense the volatile alkali. The worm-tub and 

 receiver may either be elevated higher than the steaming- 

 kettle, for the purpose of returning the condensed alkali froQi 

 time to time from the receiver into the steaming kettle, by 

 means of a tube of communication and a stopcock between 

 these two, in this manner to keep u]i a continual circulation 



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