OOHHH was my first response when this book arrived with the post: it really is small and ready to be put in your back pocket! It's tiny.
Food for Free was first published in 1972 by Richard Mabey, author of 'The Unofficial Countryside' (earlier) and it remains the absolute benchmark of wild food guides. It is totally sympathetic with its modest writing (and size) and the hearty simplicity of the information given. In 2006 Mabey wrote an article for the Guardian about the Great Forage Revival and in it reviews his own book as well, well recommended.
Wild food require none of the attention demanded by garden plants and possess the additional attraction of having to be found. I think I would rate this as perhaps the most attractive single feature of wild food use. The satisfactions of cultivation are slow and measured. They are not at all like the excitement of raking through a rich bed of cockles, of suddenly discovering a clump of sweet cicely, of tracking down a bog myrtle by its smell alone.