GPS

A Russian rocket carrying satellites failed to make orbit today, apparently. Lauching things into space has become so mundane these days the the occasional failure grabs the headlines. 

Before GPS and all this satellite foolishness we found our directions by much more basic means. Here we see the Compass, Marching, Army, Mk1

Back in the Sixties you could but this sort of stuff in WD surpus shops. they were all over the place. You don't see them these days, which is a pity. As a kid I recall them being full of loads of fantastic if useless stuff, still covered in greaseproof paper.

BTW. How does GPS work anyway? It is impossible isn't it. Answers on a postcard please.