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Chapter LVI
The Catapult, Its Construction and Management (Concluded)
How to Make and Fit the Skein of the Catapult
Fig. 199, p. 293
Insert a thin stick into the ground halfway between the winches. Place
it upright inside the framework of the catapult. This stick will serve
to keep the halves of the skein separate as it is being made, so that when
it is completed the arm of the catapult may be placed in position without
difficulty. Turn the winches till both their crossbars are perpendicular
to the ground and in line with the stick.
Next secure one end of the cord you are using for the skein to the corner
of the cross-bar of one of the winches.
Pass the other end of the cord through the holes in the sides of the
catapult and round the cross-bar of the opposite winch, and then back again
over the bar of the first winch. Do this in regular rotation to and fro,
first on one side of the stick then on the other. Be careful not to cross
the lengths of cord as you pass them between the winches, but keep them
individually straight, tight and regular and alternately on either side
of the stick, A, fig. 199, p. 293.
Do not wrap the cord at haphazard round the cross-bars of the winches,
but lay the turns regularly from one end of each cross-bar to its other
end and then back again.
When a complete layer of cord is wrapped over a cross-bar, place on
it a strip of paper 1 in. wide. By concealing the last layer the paper
will show you how to proceed with the next.1
1 The last few turns of the cord will have
to be passed through the winches by the aid of a piece of stout wire with
a loop at its end. |
