The Dyeing of Woollen Fabrics
The amount of yolk present upon different samples of wool varies greatly, the finer varieties containing, as a rule, a larger proportion than the coarser, and less valuable sorts.
The variation in the relative amount of pure fibres and yolk is (p. 007) well shown in the following analyses which, however, do not by any means represent extreme cases.
ANALYSES OF RAW MERINO WOOL. DRIED AT 100° C.
No. 1. No. 2. Moisture 6·26 10·4 Yolk 47·30 27·0 Pure Wool 30·31 59·5 Dirt 11·13 3·1 ------ ------ 100·00 100·00
Yolk consists very largely of two complex substances which have been termed wool perspiration and wool fat. The former is composed of the potash salts of fatty acids, principally oleic and stearic acids; the latter of the neutral carbohydrate, cholesterine, with other similar bodies. The wool perspiration may be removed by a simple washin