Grown men don't colour in

For a small number of people, The Blue Book is their bible, a right rivetting read; 205 pages of densely packed information and maps about the Birmingham Canal Navigations.

As it is a photocopied book, hand-made, it's possibly the worst physical production in the history of book publishing; in truth, this wasn't quite what Caxton had in mind as a vision of the future. But if you want to know which bridge on the Farmers Bridge flight had a cast-iron urinal built in to the parapet, then only the Blue Book can tell you that it is at Lancaster Street. Or was - the bridge was swept away some years ago.

The Blue Book - officially Birmingham Canal Navigations - a cruising and walking guide - is bed time reading for a rather small band of people who probably should seek professional help, but then this is the world we live in. More than ten million people watch a TV programme about a groups of real losers locked inside a house: figure that one out.

However, the Blue Book has a significant flaw. The maps are so densely packed with information that it can be difficult to work it all out. So it is accepted practice among owners (The Blue Book Owners Club) to colour in the canal part in light blue pencil.

As I have recently bought a new copy - well, a secondhand copy; the new copies are long gone - I am in the process of colouring it in. This can get a little tedious, so I have taken to doing it on the train in the mornings and evenings.

Yesterday morning, a man got on at Harlow Town, sat down opposite me, gazed in astonishment at me colouring in my Blue Book and said "Grown men don't colour in books, mate!", shaking his head.

Yeh, right. Like someone who chose to live in Harlow can advise on current trends.