Here is good supplementary reading for those interested in Hogben's first section (Conquest of Time Reckoning and Space Measurement). It is not a book for the unscientific-minded, however, for it seems abstract and highly specialized for the lay reader, and I must confess that -- until I had read the Hogben chapters on the subject, I found it incomprehensible. (Not that I didn't understand the author's language, but that the conception itself is a bit outside my normal ken). A book for you to know about -- rather than to read yourself -- for your scientific customers will want it.