Part of a .........

This is the main part of a dead reckoning computer, used by aviator chappies when facing the dreaded threat of actually having to fly to earn a few moolah. On top is a Chinagraph pencil, one of those wax pencil thingys that you can use to write on the nice shiny kneepads that come with flying overalls. Check out William's next time they show him beside his aircraft. "Wills L Kate" all over the thing.

I've spent a pair of hours out in the garage creating a light box, so hopefully tomorrow I'll show the civilain version, ancient for the use of, and explain some of the uses. For now I'm offski to a glass of Merlot and some cheese straws, cos I is knackered.