Page:History of the Royal Society.djvu/329

 '6. That some Colours, as Mather, Indico, and Woad, by reiterated tinctures, will at last become black.

'7. That although Green be the most frequent and common of natural Colours, yet there is no simple ingredient, which is now used alone, to dye Green with upon any Material; Sap-green (being the condensated juice of the Rhamnous Berry) being the nearest; the which is used by Country People.

'8. There is no black thing in use which dyes black, tho' both the Coal and Soot of most things burnt or scorched be of that colour; and the blacker, by how much the matter before it was burnt was whiter, as in the famous instance of Ivory black.

'9. The tincture of some Dying Stuffs will fade even with lying, or with the Air, or will stain even with Water; but very much with Wine, Vinegar, Urine, &c.

'10. Some of the Dyers Materials are used to bind and strengthen a Colour, some to brighten it, some to give lustre to the Stuff, some to discharge and take off the Colour either in whole or in part, and some out of fraud, to make the Material dyed (if costly) to be heavier.

'11. That some Dying Ingredients or Drugs, by the coarseness of their Bodies, make the thread of the dyed Stuff seem coarser; and some by shrinking them, smaller, and some by levigating their Asperities, finer.

'12. Many of the same Colours are dyed upon several Stuffs with several Materials; as Red-wood is used in Cloth, not in Silks; Arnotto in Silks, not in Cloth; and may be dyed at several prices.

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