The selection of books for a public library is a delicate and responsible duty, involving wider literary and scientific knowledge than falls to the lot of most trustees of libraries. There are sometimes specially qualified professional men or widely read scholars on such boards, whose services in recruiting the library are of great value. More frequently there are one or more men with hobbies, who would spend the library funds much too freely upon a class of books of no general interest. Thus, one trustee who plays golf may urge the purchase of all the various books upon that game, when one or at most two of the best should supply all needful demands. Another may want to add to the library about all the published books on the horse; another, who is a physician, may recommend adding a lot of medical books to the collection, utterly useless to the general reader. Beware of the man who has a hobby, either as librarian or as library trustee; he will aim to expend too much money on books which suit his own taste, but which have little general utility. Two mischiefs result from such a course: the library gets books which very few people read, and its funds are diverted from buying many books that may be of prime importance. Trustees, although usually, (at least the majority of them) persons of culture and intelligence, cannot be expected to be bibliographers, nor to be familiar with the great range of new books that continually pour from the press. They have their own business or profession to engage them, and are commonly far too busy to study catalogues, or to follow the journals of the publishing world. So these busy men, charged with the oversight of the library interests, call to their aid an expert, and that expert is the librarian. It is his interest and his business to know far more than they do both of what the library already contains, and what it most needs. It is his to peruse the critical journals and reviews, as well as the literary notices of the select daily press, and to be prepared to recommend what works to purchase. He must always accompany his lists of wants with the prices, or at least the approximate cost of each, and the aggregate amount. If the trustees or book committee think the sum too large to be voted at any one time from the fund at their disposal, the librarian must know what can best be postponed, as well as what is most indispensable for the immediate wants of the library. If they object to any works on the list, he should be prepared to explain the quality and character of those called in question, and why the library, in his judgment, should possess them. If the list is largely cut down, and he considers himself hardly used, he should meet the disappointment with entire good humor, and try again when the members of the committee are in better mood, or funds in better supply.