"... don't know much trigonometry" sang Herman's Hermits, but I do! The Science section of Bibiliophile is one of my favourites. As part of the international trend of publishing, many science books are published by groups that have both UK and US branches. A lot of science books are originated in the US, which means we have to put up with center, fiber, color, meter the ambiguous term meaning either 100cm or the box with terminals and a numerical display. But many American books are "popular", which is fine, but not very deep. Is there any way for Bibliophile's reviewers to flag up the level of the text? A one-letter code would do:- P = popular, A = academic, etc.