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SeE Clearer soe VI. 
Of the Colouring Matter of Linen Yarn and its Solvents, 
Havine, through the obliging attention of Mr. ArsuTuNot, 
procured a fufficient quantity of alkaline ley faturated with this 
colouring matter, or, as the workmen call it, &7//ed, and which 
they are in the habit of throwing away; I found it to be a 
turbid liquor, of a reddifh brown colour, a peculiar tafte and 
ftrong fmell, affording no fign either of acidity or alkalefcence. 
On five quarts of this liquor 1 poured two ounces of weak marine 
acid; there was no effervefcence, but a copious depofition inftantly 
took place of a greyifh green colour, and the liquor freed from this 
depofit was of the colour of red amber. 
Tue next day I drew off the liquor with a fyphon, and poured 
two quarts of pure water on the depofited matter, and having 
agitated the whole, fuffered this matter again to fubfide, drew off 
the water, and added two quarts more; this liquor gave manifeft 
figns of acidity, and continued fomewhat reddith. Prefuming 
that after the addition of fo much water this acidity could not 
proceed from the fmall quantity of marine acid I had ufed, more 
efpecially as the liquor originally contained an alkali, in the 
faturation of which the greater part of the acid muft have been 
employed, I began to fufpe& that this ley contained an acid of 
its own, which was difengaged and feparated from the alkali by 
the marine acid as thé more powerful of the two; and hence I 
referved 
