For anyone interested I've just noticed that BBC 4 is showing 'A Very British Map: The Ordnance Survey Story' next Wednesday 9 September 9pm - 10pm -
"The history of a quintessentially British institution, which was formed in 1791, originally for military reasons before becoming a valuable tool in peacetime for ramblers and adventurers. Timeshift examines how the OS is adjusting to the digital age, with the large folding maps now just a small part of its output.'