alkaline solution, one of carbonate of soda, free from any caustic, to
remove all grease, then with water to remove alkali; and my belief is
that a weaker and less acid solution of nitric acid and nitrate of
mercury, and a smaller quantity of it, would then do the work required,
and do it more uniformly.

A question frequently asked is: "Why will dead wool not felt?" Answer:
If the animal become weak and diseased, the wool suffers degradation;
also, with improvement in health follows _pari passu_, improvement in
the wool structure, which means increase both in number and vigour of
the scales on the wool fibres, increase of the serrated ends of these,
and of their regularity. In weakness and disease the number of scales in
a given hair-shaft diminishes, and these become finer and less
pronounced. The fibres themselves also become attenuated. Hence when
disease becomes death, we have considerably degraded fibres. This is
seen clearly in the subjoined figures (see Fig. 13), which are of wool
fibres from animals that have died of disease. The fibres are attenuated
and irregular, the scale markings and edges have almost disappeared in
some places, and are generally scanty and meagre in development. It is
no wonder that such "dead wool" will be badly adapted for felting. "Dead
wool" is nearly as bad as "kempy" wool, in which malformation of fibre
has occurred. In such "kemps," as Dr. Bowman has shown, scales have
disappeared, and the fibre has become, in part or whole, a dense,
non-cellular structure, resisting dye-penetration and felting (see Fig.
14).

[Illustration: FIG. 13.]

[Illustration: FIG. 14.]