Well, Leonardo's tank finished it's tour of the far reaches of the earth and arrived on my doorstep today. Actually, it arrived at my front gate, and the DHL left the front gate open, which subsequently meant that the Dingo (Claudius) who had been outside sunning himself, decided to take the opportunity to go out for a walkabout around southern California...
Fortunately, both Claudius and Leonardo's tank are here, safe and sound, at the moment. This is a real gem of a piece, and it's a breeze to put together. Only separate bits are the cannon barrels. Methinks this will do well, me does. Hope to have it off to the caster, soon, but I'm still waiting for them to master the Filatov.
And incidentally, the most recent tests on Leonardo's design have shown that it -would- have worked. The problem with earlier tests was that not all testers realized DaVinci's little "trick". In addition to writing backwards, many gears were placed -backwards- so that someone who wanted to steal the design would fail at replicating it. It's amazing how many of Leonardo's designs have since been found to be quite workable by simply reversing the position of a gear, switching part "a", with part "b", etc.
-Doc