THE STRINGING AND TUNING OF CATAPULTS
1. Beams of very generous length are selected, and upon them are nailed
socket-pieces in which windlasses are inserted. Midway along their
length the beams are incised and cut away to form framings, and in these
cuttings the capitals of the catapults are inserted, and prevented by
wedges from moving when the stretching is going on. Then the bronze
boxes are inserted into the capitals, and the little iron bolts, which
the Greeks call [Greek: epizygides], are put in their places in the
boxes.
2. Next, the loops of the strings are put through the holes in the
capitals, and passed through to the other side; next, they are put upon
the windlasses, and wound round them in order that the strings,
stretched out taut on them by means of the handspikes, on being struck
by the hand, may respond with the same sound on both sides. Then they
are wedged tightly into the holes so that they cannot slacken. So, in
the same manner, they are passed through to the other side, and
stretched taut on the windlasses by means of the handspikes until they
give the same sound. Thus with tight wedging, catapults are tuned to the
proper pitch by musical sense of hearing.
On these things I have said what I could. There is left for me, in the
matter of sieges, to explain how generals can win victories and cities
be defended, by means of machinery.