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is raised four fories in height, in the upper story of which the scorpions and catapultas are 
dipoled; in thole below a great quantity of water is collected, to extinguilh fire if it should 
happen to be thrown therein. 
In this allo was the ram machine, in Greek called cridoche, wherein were laid rollers per- 
fectly turned, upon which was disposed the ram; the drawing of which backward and forward 
with ropes, produced the great effect : this also was covered with raw hides, in the same 
manner as the tower. 
Concerning the Borer he has given these rules in writing:—The machine is the 
Fig. CXII. 
same as the tortoise, having in the middle a straight channel (A), like those usually 
made in the catapultae or balistae, of the length of L. cubits, and in height one cubit. In 
this is fixed a transverse windlass (B), and at the end, on the right and left, two trochlea 
(lheaves of pulleys), by which the beam, armed with iron at the part (C) that lies at the 
end of the channel, is moved. Under the same (beam), included within the channel, are 
rollers, which cause the motion to be quicker and more vehement; and over the beam that is 
therein are fixed arched ribs (D), to bear the raw hides (E) with which the machine is 
covered, to defend the channel. 
Of the Crow he has not thought proper to write, because he had observed this machine to 
be of no use. 
Of the Accessus, which in Greek is called epibathra, and of the marine machines for 
(5*) In the text it is written tuti, which is corrected 
by De Lact to tori : for Atheneus, in this place, writes 
cylindroi; and at the place foregoing, where Vitruvius 
mentions torus, cylindron; so that, as the same thing is ex¬ 
pressed by Atheneus, it is highly probable that the same 
thing is meant by Vitruvius, in both places; the rather as 
the correction agrees perfectly with the sense and meaning 
of the context. 
(6*) Apollodorus, Heron, and other antient authors, 
have described a machine of this name; and Polybius 
gives an account of one that was invented by the Romans 
at the time of their first naval engagement against the 
Carthaginians, with which they grappled the enemies 
ships, and by that means chiefly obtained the victory. 
(7*) The commentators think the word accessu should 
be written ascensu, supposing it to signify a machine for 
scaling the walls of a town; and Perrault, as well as 
Galiani, have so translated it. But I find it plainly written 
accessu in all the manuscripts I have seen: and it is well 
known that the antients had machines for gaining access 
to the bottom of the walls, in order to undermine them, 
or fill up the ditches. Julius Cæsar mentions one that 
he used at the siege of Marseilles, called a musculus; and 
Vitruvius describes one in the following chapter by the 
name of testudo, mentioning its use by the very words 
accessus ad murum. The antients, it is true, had also 
machines for scaling the walls; but since they had ma¬ 
chines for both these purposes, there is no reason to suppose 
that the word that clearly expresses the one, should have