Species of Galium
(CHAPTER I. The Anthraquinone Group.)

The Natural Organic Colouring Matters
Arthur George Perkin, F.R.S., F.R.S.E., F.I.C., professor of colour chemistry and dyeing in the University of Leeds
Arthur Ernest Everest, D.Sc., Ph.D., F.I.C., of the Wilton Research Laboratories; Late head of the Department of Coal-tar Colour Chemistry; Technical College, Huddersfield
Longmans, Green and Co.
39 Paternoster Row, London
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Bombay, Calcutta, and Madras

(Tekstiin lisätty kappaleita lukemisen helpottamiseksi. // Some paragraphs added to the original text for making reading easier.)

Kaikki kuvat (kemialliset kaavat) puuttuvat // None of the illustrations (of chemical formulas) included.

The roots of various species of galium have been employed to some extent for dyeing red on aluminium mordant, and Bancroft in his "Philosophy of Permanent Colours" (vol. ii., 303) mentions six of these plants, the roots of which gave an excellent red in this manner. More especially he refers to the Galium tinctorium, the roots of which, about 2 feet in length, are of a dark reddish colour, and which were employed by the French inhabitants of Canada to dye their cloths red.

This product is also referred to by Hellot, p. 161, as a species of madder brought from Canada which possesses an extremely slender root and produces nearly the same effect as European madder.

According also to Bancroft the roots of the nearly allied species of Asperula, of which he specially mentions the Asperula tinctoria known as "Dyer's woodruff," were at one time used for dyeing red instead of madder (p. 307).

Of others may be mentioned the Galium mullugo, Great Ladies' bedstraw or Wild madder, Galium verum, Yellow Ladies' bedstraw, and Galium aparine, the well-known Cleaver's or Goose grass, the two latter of which are common to this country. The roots of this last certainly give a small amount of dye soluble in alkali with a purple colour, and there seems to be little doubt that all contain dyes which are fast to light and of the alizarin type, though they appear to give a somewhat yellower shade than alizarin itself. An examination of these in case they yield either anthrapurpurin or flavopurpurin would be interesting.

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