facture, most yarns are utilized in the form
they leave the spinning frame, that is, as single yarns. On the
other hand, for certain branches of the trade, weaving included, it
is necessary to take two, three, or more of these single yarns and to
combine them by a process technically termed twisting, and sometimes
"doubling" when two single yarns only are combined.

Although the commonest method, so far as weaving requirements go, is
to twist two single yarns together to make a compound yarn, it is
not uncommon to combine a much higher number, indeed, sixteen or
more single yarns are often united for special purposes, but, when
this number is exceeded, the operation comes under the heading of
twines, ropes and the like. The twist or twine thus formed will have
the number of yarns regulated by the levelness and strength required
for the finished product. The same operation is conducted in the
making of strands for cordage, but when a number of these twines are
laid-up or twisted together, the name cord or rope is used to
distinguish them.[1]

[Footnote 1: See _Cordage and Cordage Hemp and Fibres_, by T.
Woodhouse and P. Kilgour.]

When two or three threads are united by twisting, the operation can
be conducted in a twisting frame which differs little from a
ordinary spinning frame, and hence need not be described. There may
be, however, appliances embodying some system of automatic stop
motion to bring the individual spindles to rest if one thread out of
any group which are being combined happens to break. When several
threads have to be twisted together, special types of twisting
frames are employed; these special machines are termed "tube twisters,"
and the individual threads pass through holes suitably placed in a
plate or disc before they reach the tube.

More or less elaborate methods of combining yarns are occasionally
adopted, but the reader is advised to consult the above-mentioned
work on Cordage and similar literature for detailed information.

When the yarn leaves the spinning frame, or the twisting frame, it
is made up according to requirements, and the general operations
which follow spinning and twisting are,--reeling, cop-winding, roll
or spool winding, mill warping or link warping. The type or class of
yarn, the purpose for which the yarn is to be used, or the equipment
of the manufacturer, determines which of these methods should be
used previous to despatching the yarn.

_Reeling_. Reeling is a