As a project for this Christmas holiday, I built working miniature replicas of three medieval siege engines -- a catapult, a trebuchet, and a ballista.

The catapult was constructed first, and was by far the easiest. The release mechanism makes no pretence at imitating the original, and consists solely of a couple of blocks designed to hold the lever down while a marble or piece of cheese or whatever is placed in the (rather flat) cup. If I think I have time, I may go back and add some thread to the end of the arm, to provide something more appropriate with which to pull it down. Except that, to maintain the miniature realism, I'd then have to construct a windlass to which the thread could be attached, and parts for which are not provided with the kit. Poot!

    

The ballista was constructed next, although it turned out to be the most difficult of the three and the one which I eventually had to fudge: the ratchets to support the ropes to which the bow arms are attached are designed in such a way that they can't withstand the tension produced by the elastic, which kept pulling the pegs out. So the elastic bands had to be replaced by cotton thread, which can be twisted sufficiently to keep the bow arms in place but not enough to provide any power for the bow itself -- or not enough to shoot the missile more than a couple of feet, anyway. But at least it looks right.

    

The last of the three was the trebuchet, which looked hideously complicated from the instructions but was actually intermediate between the other two. The working model I'd seen in the shop where I'd purchased the kits (and indeed the model which had inspired the purchase in the first place) had replaced the wooden sling-end with a leather cup attached with a piece of string; it looked very good (and is probably more effective than the wooden sling-end provided with the kit -- again, if I think I have time, I may go back and install a string-and-leather cup on my model). The gravel which fills the box was specially selected from our garden path, and hand-washed before installation.

    

A final photograph of all three miniature replicas with which to finish: