our digits thick, is put under the block. The blocks
used have each three rows of sheaves side by side. Hence three traction
ropes are fastened at the top of the machine. Then they are brought to
the block at the bottom, and passed from the inside round the sheaves
that are nearest the top of it. Then they are brought back to the upper
block, and passed inwards from outside round the sheaves nearest the
bottom.

9. On coming down to the block at the bottom, they are carried round its
second row of sheaves from the inside to the outside, and brought back
to the second row at the top, passing round it and returning to the
bottom; then from the bottom they are carried to the summit, where they
pass round the highest row of sheaves, and then return to the bottom of
the machine. At the foot of the machine a third block is attached. The
Greeks call it [Greek: epagon], but our people "artemon." This block
fastened at the foot of the machine has three sheaves in it, round which
the ropes are passed and then delivered to men to pull. Thus, three rows
of men, pulling without a capstan, can quickly raise the load to the
top.

10. This kind of machine is called a polyspast, because of the many
revolving sheaves to which its dexterity and despatch are due. There is
also this advantage in the erection of only a single timber, that by
previously inclining it to the right or left as much as one wishes, the
load can be set down at one side.

All these kinds of machinery described above are, in their principles,
suited not only to the purposes mentioned, but also to the loading and
unloading of ships, some kinds being set upright, and others placed
horizontally on revolving platforms. On the same principle, ships can be
hauled ashore by means of arrangements of ropes and blocks used on the
ground, without setting up timbers.

11. It may also not be out of place to explain the ingenious procedure
of Chersiphron. Desiring to convey the shafts for the temple of Diana at
Ephesus from the stone quarries, and not trusting to carts, lest their
wheels should be engulfed on account of the great weights of the load
and the softness of the roads in the plain, he tried the following plan.
Using four-inch timbers, he joined two of them, each as long as the
shaft, with two crosspieces set between them, dovetailing all together,
and then leaded iron gudgeons shaped like dovetails into the ends of the
shafts, as dowels are leaded, and in the woodwor