A message to librarians

Attention: In mathematics, the fact that a book has a new edition by no means whatsoever should be taken to imply that the old edition should be discarded! (Just because it works that way in some subjects doesn't mean that it works that way in every subject. Some of them haven't exactly changed much in a while...)

The Somerville library ("Library!") was discarding some old mathematics books in the interest of space (which I appreciate is necessary). I took some of these myself because I think that there is a chance that I might have some use for them (even if it's only on a rare occasion) and a few of them I insisted that they put back because the student demand for them already outstrips the supply. (A couple of the books I rescued are ones I don't expect to use at all, but I have historical interest in them for various reasons.) Throwing these away would then exacerbate a problem that already exists. One of the books that I so rescued was this one (technically, the same edition but under a different publisher). Unbelievable...