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prepared a considerable time before it is used, its colourbeing found to improve in keeping.

The logwood decoction being made of a scalding heat,but not quite boiling, the vitriol is thrown into it, andas soon as this is dissolved, the galled cloth is put in. Aboiling heat should never be used after the addition ofthe vitriol, not only as it would needlessly augment thecorrosive power of the fait, but likewise as it would injurethe beauty of the colour, by hastily extricating part of theferrugineous matter of the vitriol in an ochery form, beforeit can come sufficiently in contact with the astringentsubstance with which the cloth is impregnated. Thecloth is incessantly turned in the liquor that it may receivethe colour uniformly, and now and then taken out andaired for a moment, which contributes to secure thecolour, and at the same time affords an opportunity ofjudging of its deepness.

After about two hours continuance in the dye, thecloth is found to have received a good black, and is thentaken out, washed with cold water, and passed throughthe fulling mill. The superfine cloth is three times fulled,with warm solution of soap, which not only dischargesthe superfluous colour that would otherwise stain the skinor linen, but contributes also to soften the cloth itself bymortifying the acid.

III. Black dye with vcrdegris.

For some of the superfine black cloths, a little verdegrisis used by our dyers, and this addition appears among theFrench to be more frequent. Mr. Hellot, after trial ofsundry processes, gives the following as being the best, oras that which produces the finest velvet black on cloth,and which accordingly is followed in the best dye-housesin Franee,

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