Siegecraft - TerpConnect - University of Maryland

Parangelmata Poliorcetica
both are measured by a common measure. For thrice 30 measures
90, and twice 60; and again thrice 8 measures 24, and
twice 8, 16. And as 90 is to 60, so 24 is to 16; and as 24 is to 16,
so also are the wheels to one another in number and in size, and
the base is to the base, as also 3 to 2. The measuring
then have been shown to mutually have the same ratio proportionally
to those being measured. And so the of
Apollodorus, in carrying out the construction of his portable
towers, will be found not only commensurable but in harmony
with of Diades and Charias. And it is clear that the
ancient engineers and the very learned master builders carried
out the construction of machines scientifically and rationally.
39. When the construction of the tower is thus completed, if
the area lying under the base should not be even and level, but
happens to slope upward, we shall make a counterplate at the
base of the tower with the same intertwined as
it; this comes up against the irregularity of the earth and amplifies
the area lying below, so that the tower may be maintained
steadfast in position when turbulent battle is joined. It will be
guarded against burning from fire-bearing caltrops launched
and from ignited flames if boards are nailed on,
especially of palm or others of strong wood, except cedar, fir, and
alder, as these easily burn, break, and shatter. Hides should be
hung on the tower at the ledges and galleries, which were already
mentioned during the construction , not right
up against the boards, but a little bit away from them because of
the incendiaries and so that the blows of the stone throwers on
the hollow space may be weak against these and dissipated
with the slackening of the momentum. The tower should
be fitted with nails on top, as was discussed earlier in the case of
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