Water alone will
wash out a considerable amount of this greasy matter, forming a kind of
lather with it, but not all. As is almost invariably the case, after
death, the matters and secretions which in life favour the growth and
development of the parts, then commence to do the opposite. It is as if
the timepiece not merely comes to a standstill, but commences to run
backwards. This natural grease, if it be allowed to stand in contact
with the wool for some time after shearing, instead of nourishing and
preserving the fibres as it does on the living animal, commences to
ferment, and injures them by making them hard and brittle. We see, then,
the importance of "scouring" wool for the removal of "yolk," as it is
called, dirt, oil, etc. If this important operation were omitted, or
incompletely carried out, each fibre would be more or less covered or
varnished with greasy matter, resisting the absorption and fixing of
mordant and dye. As scouring agents, ammonia, carbonate of ammonia,
carbonate of soda completely free from caustic, and potash or soda
soaps, especially palm-oil soaps, which need not be made with bleached
palm oil, but which must be quite free from free alkali, may be used.
Pages:
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174