temperature than
113 deg. F., and the apparatus ought to be provided with an agitator; 2nd,
the cleansing or scouring proper, with a weak alkaline solution; 3rd,
the rinsing or final washing in water.

Thus far we have proceeded along the same lines as the woollen
manufacturer, but now we must deviate from that course, for he requires
softness and delicacy for special purposes, for spinning and weaving,
etc.; but the felt manufacturer, and especially the manufacturer of felt
for felt hats, requires to sacrifice some of this softness and delicacy
in favour of greater felting powers, which can only be obtained by
raising the scales of the fibres by means of a suitable process, such
as treatment with acids. This process is one which is by no means
unfavourable to the dyeing capacities of the wool; on the whole it is
decidedly favourable.

So far everything in the treatment of the wool has been perfectly
favourable for the subsequent operations of the felt-hat dyer, but now I
come to a process which I consider I should be perfectly unwarranted in
passing over before proceeding to the dyeing processes. In fact, were it
not for this "proofing process" (see Lecture VII.) the dyeing of felt
hats would be as simple and easy of attainment as the ordinary dyeing of
whole-wool fabrics. Instead of this, however, I consider the hat
manufacturer, as regards his dyeing processes as applied to the stiffer
classes of felt hats, has difficulties to contend with fully comparable
with those which present themselves to the dyer of mixed cotton and
woollen or Bradford goods. You have heard that the purpose of the
wool-scourer is to remove the dirt, grease, and so-called yolk, filling
the pores and varnishing the fibres. Now the effect of the work of the
felt or felt-hat proofer is to undo nearly all this for the sake of
rendering the felt waterproof and stiff. The material used, also, is
even more impervious and resisting to the action of aqueous solutions of
dyes and mordants than the raw wool would be. In short, it is impossible
to mordant and to dye shellac by any process that will dye wool. To give
you an idea of what it is necessary to do in order to colour or dye
shellac, take the case of coloured sealing-wax, which is mainly composed
of shellac, four parts, and Venice turpentine, one part. To make red
sealing-wax this mixture is melted, and three parts of vermilion, an
insoluble metallic pigment, are stirred in. If black sealing-wax