achine................................... 208

33. Experimental Dye Apparatus............................. 212

CHAPTER I. (p. 001)

THE WOOL FIBRE.

Wool is one of the most important textile fibres used in the
manufacture of woven fabrics of all kinds. It belongs to the group of
animal fibres of which three kinds are met with in nature, and used in
the manufacture of textile fibres; two of these are derived from
quadruped animals, such as the sheep, goat, etc., while the third
class comprises the products of certain insects, _e.g._, silk.

The skin of all animals is covered with more or less of a fibrous
coat, which serves as a sort of protecting coat from the weather to
the skin underneath. Two different kinds of fibres are found on
animals; one is a stiff kind of fibre varying in length very much and
called hairy fibres, these sometimes grow to a great length. The other
class of animal fibres are the woolly fibres, short, elastic and soft;
they are the most esteemed for the manufacture of textile fabrics, it
is only when the hairy fibres are long that they are serviceable for
this particular purpose. There is a slight difference in the structure
of the two kinds of fibre, woolly fibres having a more scaly structure
than hairy fibres; the latter also differ in being more cylindrical in
form.

#Wool.#--By far the most important of the animal fibres is wool, the
fibre of the domestic sheep. Other animals, the llama or alpaca, the
Angora and Cashmere goats also yield fibres of a similar character,
which are imported under the name of wools. There are many (p. 002)
varieties of wools Which are yielded by the various breeds of sheep,
but they may be roughly divided into two kinds, according to the
length of "staple," as it is called. In the long-stapled wools the
fibres average from 7-1/2 to 9-1/2 inches in length, while the
short-stapled wools vary from 1 to 2 inches long. The diameter varies
very considerably from 0.00033 to 0.0018 of an inch.

[Illustration: Fig. 1.--Wool Fibre under the Microscope.]

Two varieties of thread are spun from wool, one is known as "worsted,"
the other as "woollen" yarns; from these yarns two kinds of cloths are
woven, distinguished as worsted and woollen cloths; the former are in
general not subjected to any milling or felting process, while the
latter invariably are.

#Physical Properties.#--When seen under t