_A_. Hence, the cloths _H_, _B_ and _T_ can be woven without
any mechanical alteration in the loom.

_C_ is the 3-leaf double warp sacking weave and shows 4 units;
since each pair of vertical rows of small squares consists of two
identical single rows, they may be represented as at _D_. The actual
structure of the cloth _S_ in Fig. 32 is represented on design paper
at _C_, Fig. 33.

_D_ is the single warp 3-leaf sacking weave, 4 units shown, but
the mechanical parts for weaving both _C_ and _D_ remain constant.

_E_ is the double warp 4-leaf sacking, 2 units shown, while

_F_ is the single warp 4-leaf sacking, 4 units shown.

The patterns or cloths for _E_ and _F_ are not illustrated.

_G_ is a "herring-bone" design on 24 threads and 4 picks, two
units shown. It is typical of the pattern represented at _C_, Fig. 32,
and involves the use of 4 leaves in the loom.

The solid squares in weave _A_, Fig. 33, are reproduced in the
left-hand bottom corner of Fig. 34. A diagrammatic plan of a plain
cloth produced by this simple order of interlacing is exhibited in
the upper part by four shaded threads of warp and four black picks
of weft (the difference is for distinction only). The left-hand
intersection shows one thread interweaving with all the four picks,
while the bottom intersection shows all the four threads
interweaving with one pick. The two arrows from the weave or design
to the thread and pick respectively show the connection, and it will
be seen that a mark (solid) on the design represents a warp thread
on the surface of the cloth, while a blank square represents a weft
shot on the surface, and _vice versa_.

A weaving shed full of various types of looms, and all driven by
belts from an overhead shaft, is illustrated in Fig. 35. The loom in
the foreground is weaving a 3-leaf sacking similar to that
illustrated at _S_, Fig. 32. while the appearance of a full weaver's
warp beam is shown distinctly in the second loom in Fig. 35. There
are hundreds of looms in this modern weaving shed.

[Illustration: FIG. 35 WEAVING SHED WITH BELT-DRIVEN LOOMS]

During the operation of weaving, the shuttle, in which is placed a
cop of weft, similar to that on the cop winding machine in Fig. 25,
and with the end of the weft threaded through the eye of the shuttle,
is driven alternately from side to side of the cloth through the
opening or "shed" formed by two layers of the warp. The positions of
the threads in these two laye