One could be forgiven for thinking that a leaf book, if it wasn’t a tree-identification manual, was a large volume used for pressing plants between sheets of blotting paper. Plant collectors seem to have moved on a bit from such rough and ready tools. The first item in The American Museum of Natural History’s instructions on How to Press and Preserve Plants reads “Buy or build a plant press”. Nothing about looking for a heavy tome.

A leaf book is actually a book containing one leaf (2 pages) from a famous book surrounded by suitable commentary and fluff. For example 2 pages from a Gutenberg Bible surrounded by pages telling you how well Gutenberg’s presswork was executed, how he invented movable metal types etc. etc. Truly a publication for the collector: just not the botanical sort. In ABC for book collectors John Carter explains a leaf book succinctly.

“A leaf book is (or was – they are out of fashion) a way of making a silk purse out of a sow’s ear. A seriously imperfect copy of a famous book presented the opportunity: some suitable authority on the book would be asked to write an essay on it, a distinguished printer would be asked to give it typographic form, choosing a page slightly larger than that of the book in question, and printing as many copies as there were surviving leaves. The whole would be handsomely bound, with one leaf of the original laid in. A Noble Fragment 1921, in which this treatment was bestowed on over 200 leaves (about a third of the whole) of a copy of Gutenberg’s 42-line Bible, was the original leaf book. The evidential (not to say monetary) value of a single leaf of that Bible is now so great as to make this seem deplorable vandalism; at the time, no doubt, it was regarded as an honest way to bring to a larger market something in itself virtually unsaleable. Hard cases make bad law: a leaf book is always in some way a hard case. But breaking-up is not to be condoned, even in a good cause.”