trebuchet, however large, as work merely by a counterpoise, and that of an engine deriving its power from the elasticity of an immense coil of tightly twisted sinew.

It is certain that if the latter kind of engine had survived in its perfect state the introduction of the cannon would have been considerably delayed, for the effects in warfare of the early cannon were for a long period decidedly inferior to those of the best projectile engines of the ancients.

Notwithstanding many difficulties, I have succeeded in reconstructing, though of course on a considerably smaller scale, the chief projectile throwing engines, and with a success that enables them to compare favourably, as regards to their range, with the Greek and Roman weapons they represent,

Still, my engines are by no means perfect in their mechanism, and are, besides, always libel to give way under the strain of working.

One reason of this is that all modern engines of the kind require to be worked to their utmost, i.e. to the verge of their breaking point, to obtain from then results that at all equal those of their prototypes.

A marked difference between the ancient engine and their modern imitations, however excellent the latter may be, is, that the former did their work easily, and well within their strength, and thus without any excessive strain, which might cause their collapse after a short length of service.¹

The oft-disputed question as to the distances to which the catapults and ballistas shot their projectile scan be solved with approximate accuracy by comparing their performances - as given by ancient military writers - with the results obtainable from modern reproductions.

While treating of this matter we should carefully consider the position and surroundings of the engines when engaged in a siege, and especially the work for which they were designed.

As an example, archers, with the advantage of being stationed on high towers and battlements, would be well able to shoot arrows from 270 to 280 yards. For this reason it was necessary for safe manipulation of the attacking engines that they be placed about 300 yards from the outer walls of any fortress they were assailing.

As a catapult or balista was required not only to cast its missile among the soldiers on the ramparts of a fortified place, but also to send it clear over the walls amid the houses and people within the defences, it is evident that the

¹ Again, though my largest catapult will throw a stone to a great distance it cannot throw one of nearly the weight it should be able to do, considering the size of its frame, skein of cord and mechanism. In this respect it is decidedly inferior to the ancient engine.