First published in 1958. You'll no doubt be stunned to learn that this edition dates from the early 70s. The description on the back is probably the most enticing I've ever read.
Essentially it's a child's guide to becoming an ill-fated M R James character. The book's full title is Looking and Finding and Collecting and Reading and Investigating and Much Else. Which I'm sure you'll agree is a pretty neat summation of what we do here at Mounds and Circles. Especially the "Much Else" bit.