For many years I've been trying to fathom out the reference library's shelving scheme and failing miserably. The books are given Dewey numbers but aren't shelved in Dewey order. Each is given a numbered sticker. If you consult the library catalogue you'll get the Dewey number but not the number on the sticker. To get that, you have to know the title of the book you want and then go over to a card index on the window ledge (I kid you not) to find the number. Thank God! they are shelved in numerical order.
But what order is it? It isn't anything obvious like author or subject matter. Nor date of publication as the 2005 Writer's Yearbook sits next to a health service directory published in 1997. Publisher? No. A few of us got talking about this recently and picked holes in our respective theories. In the end we had to ask Reggie Clockwatcher as it was driving us barmy and putting Frog off his crosswords. I felt like Doctor Watson being deflated as Sherlock Holmes explained the trick. So very, very obvious.
The books are shelved in order of height.