The Engineer's and Mechanics Encyclopædia: Logwood.

The Engineer's and Mechanics Encyclopædia,
comprehending practical illustrations of the machinery and processes employed in every description of manufacture of the British Empire.
With nearly Two Thousand Engravings.
By Luke Hebert, civil engineer, edifor of the History and Progress of the Steam Engines, Register of Arts and Journal of Patent Inventions, etc.
In two volumes.
London: Thomas Kelly, 17, Paternoster Row.
A hard compact wood, so heavy as to sink in water; of a fine grain, capable of being polished, and so durable, as to be scarcely susceptible of decay. Its predominant colour is red, tinged with orange, yellow, and black. It yields its colour both to spirituous and watery menstrua. Alcohol extracts it more readily and copiously than water. The colour of its dye is a fine red, inclined a little to violet or purple, which left to itself, becomes yellowish, purple, and at length black. Acids turn it yellow, alkalies deepen the colour, and give it a purple or violet hue. A blue colour is obtained from logwood, by mixing verdigris with it in the dye bath. The great consumption of logwood is for blacks, to which it gives a lustre and velvety cast; it is also extensively used as a red, purple, or black dye to beech, and various white woods.

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