Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 edition. Excerpt: ...it dissolves readily; in 7 per cent. sulphuric acid it is very easily soluble, as also in the concentrated acid; in very dilute hydrochloric acid it is easily soluble, in 5 per cent. less so, in 10 per cent. but little soluble, and in 20 per cent. almost insoluble. When ferric chloride is added to an alcoholic solution, a fine blue colour is produced, which on dilution with water changes to blue-violet and is fairly stable. Caustic soda when added to an acid solution gives a pure blue colour that is unstable on dilution, whereas sodium carbonate produces only a blue-violet colour which is fairly permanent in these circumstances. Neutral, or basic, lead acetate produces a deep blue flocculent precipitate, and copper sulphate a dull red deposit when added to a solution of the salt. Willstatter and Zollinger described the absorption spectrum as consisting of a single broad band with ill-defined edges. They gave the following measurements for a solution of 0-015 gr. in 50 c.c. of 7 per cent. H2S04: --Column 2-5 mm. 559. 552... 543-491.. 481 5-0 587. 574.. 564-455 to end of visible. The distribution number is 1o-9, which is very slightly higher than that of most monoglucoside anthocyans, and hydrolysis yields myrtillidin chloride (1 mol.) and galactose (1 mol.). Myrtillin picrate, the preparation of which is described above, is difficultly soluble and crystallises in fine red needles. Althae1n. Althaein--a monosaccharide of myrtillidin--the colouring matter of the black malva (hollyhock) (Althae rosea, Cav.) has been the subject of investigation by several workers, and it would appear that some of the earliest chemical work on this pigment was encouraged by the Bavarian Government on account of the use then made of the pigment..."
