n the making of
thread or yarn from the fibrous product of the Cotton plant. Take for
instance the Carding Engine, and the bobbin and fly frames, as
previously described. So long as these machines are working, practically
all of the acting parts of the mechanism have a continuous forward
motion.

This is by no means the case with the machine now under consideration,
as many of the more important and principal parts move alternately in
opposite directions, while other of the less important may revolve at
one time, and be stationary at another.

What are called the medium counts of yarn contain say from 30 to 50
hanks in one pound avoirdupois; a cotton hank being equal to 840 yards,
so that one pound of 40's yarn will contain no less than 40 x 840 yards
or 33,600.

For such yarns as these, a modern self-actor mule would probably go
through its cycle of movements four times per minute. For coarser or
thicker yarns this speed might be increased, while for finer and better
qualities of yarn the speed would be diminished.

Now as each succeeding "stretch" marks a complete cycle of movements and
is a repetition of others, it will probably suffice if a brief
non-technical description of one of these "stretches" or "draws," as
they are termed in mill parlance, be given.

As in the bobbin and fly frames, the bobbins containing the rovings of
cotton to be operated upon, are placed behind the mules on skewers
fitted in a suitable framework of wood and iron called "creels," so as
to allow the cotton to be easily pulled off and unwound without
breaking. These rovings are guided to and drawn through three pairs of
drawing rollers (see Fig. 27), which shows this very fully.

The chief difference between these rollers and those of the previously
described machines being in the lessened diameters of the mule rollers,
and consequently attenuating the cotton to a much greater extent. It
is a truism well understood by those in the trade, that the finer the
rovings are the better the raw cotton must be, and the more drawing-out
they will stand in any one machine. One inch of roving put up behind the
rollers of a mule spinning medium numbers would probably be drawn out
into 9 inches.

Image: FIG. 27.--Mules showing "stretch" of cotton yarn.

Nothing more need be said here about the action of the drawing rollers.

As the attenuated rovings leave the roller at the front, each one is
conducted down to a spindle revolving at a high rat