Yolk consists very largely of two complex substances which have been termed wool perspiration and wool fat.
By this method all the wool fat, suint, etc., of the wool find their way into the soap liquors.
Dioscorides was also learned in the preparation of wool fat, which he calls sypum, known to modern pharmacists as lanoline.
Degras, wool fat and vaseline are greases used, and the drying and stretching finished off at 120 F.
This wool fat or lanoline is used in making soap and ointments.
The wool fat consists largely of a peculiar fat-like body known as cholesterine.