ion: Fig. 125.]

The end _a_ is brought back and dipped down through _b_ and this is
continued as long as required, finishing off by running the end through
the last bight and hauling it taut (Fig. 126).

[Illustration: Fig. 126.]

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(16). +Twist Or Plait Knot+.--Another method of shortening a small
handy rope is known as the twist or plait knot.

Arrange the rope in such a manner that the amount to be taken up forms
a bight as in Fig. 127.

[Illustration: Fig. 127. Fig. 128.]

Then by taking _a_ over _b_ and _c_ over _b_, and so on, taking the
outside one on each side alternately over the middle one, the plait is
formed. To keep the plait clear, the end has to be continually dipped
through the first bight made (Fig. 128).

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HOW TO HANDLE WIRE ROPE, ETC.

+The following article by a Wire Specialist will be read with
interest+:--

When uncoiling Wire Rope it is important that no kinks are allowed to
form, as once a kink is made no amount of strain can take it out, and
the rope is unsafe to work. If possible a turn-table should be
employed (an old cart wheel mounted on a spindle makes an excellent
one); the rope will then lead off perfectly straight without kinks.
(See Fig. 129.)

[Illustration: Fig. 129. Fig. 130.]

If a turn-table is not available the rope may be rolled along the
ground as shown in Fig. 130.

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In no case must the rope be laid on the ground and the end taken over
(as in Fig. 131), or kinks will result, and the rope will be completely
spoiled.

[Illustration: Fig. 131.]

The life of Wire Rope depends principally upon the diameter of drums,
sheaves, and pulleys; and too much importance cannot be given to the
size of the latter. Wherever possible the size of the pulleys should
be not less than 700 times the diameter of the largest wire in the
rope, and never less than 300 times. The diameters of drums, sheaves,
and pulleys should increase with the working load when the factor of
safety is less than 5 to 1.

The load should not be lifted with a jerk, as the strain may equal
three or four times the proper load, and a sound rope may easily be
broken.

Examine ropes frequently. A new rope is cheaper than the risk of
killing or maiming employees.

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One-fifth of the ultimate strength of the rope should be considered a
fair working load.

In shafts and elevators where human life is constantly raised and
lowered, the working load should not be more