Libraries are always complaining that they cannot buy many valuable books from lack of funds. Yet some of them buy a great many that are valueless in spite of this lack. Can any thing be conceived more valueless than a set of Sylvanus Cobb's novels, reprinted to the number of thirty-five to forty, from the New York Ledger? Yet these have been bought for scores of libraries, which could not afford the latest books in science and art, or biography, history, or travel. There are libraries in which the latest books on electricity, or sewerage, or sanitary plumbing, might have saved many lives, but which must go without them, because the money has been squandered on vapid and pernicious literature. In almost every library, while some branches of knowledge are fairly represented, others are not represented at all. Nearly all present glaring deficiencies, and these are often caused by want of systematic plan in building up the collection. Boards of managers are frequently changed, and the policy of the library with them. All the more important is it that the librarian should be so well equipped with a definite aim, and with knowledge and skill competent to urge that aim consistently, as to preserve some unity of plan. I need not add that a librarian should be always wide awake to the needs of his library in every direction. It should be taken for granted that its general aim is to include the best books in the whole range of human knowledge. With the vast area of book production before him, he should strengthen every year some department, taking them in order of importance. Some scholarly writers tell us that very few books are essential to a good education. James Russell Lowell named five, which in his view embraced all the essentials; namely, Homer, Dante, Shakespeare, Cervantes, and Goethe's Faust. Prof. Charles E. Norton of Harvard remarked that this list might even be abridged so as to embrace only Homer, Dante and Shakespeare. I can only regard such exclusiveness as misleading, though conceding the many-sidedness of these great writers. To extend the list is the function of all public libraries, as well as of most of the private ones. Next after the really essential books, that library will be doing its public good service which acquires all the important works that record the history of man. This will include biography, travels and voyages, science, and much besides, as well as history. Special pains should be taken in every library to have every thing produced in its own town, county, and State. Not only books, but all pamphlets, periodicals, newspapers, and even broadsides or circulars, should be sought for and stored up as memorials of the present age, tending in large part rapidly to disappear.