The mere clerical work of maintaining an efficient reserve system is large, its success being dependent upon intelligent co-operation between the teaching faculty and the library, but it involves also a technical problem to be solved by the librarian. What relation does the number of copies of a given reserve book bear to its use? To put the question concretely, how many copies of a book are required to supply a class of 200 students, all of whom must read thirty pages of the book within two weeks? I like so much one of Mr. Hicks’s expressions that I desire to emphasize it at the close of what I am saying. A library, used for teaching purposes in a school, is indeed, “a composite textbook.” It insures contact with a composite instead of a single mind. The old idea was that contact of this kind always resulted in confusion--in mental instability. There was a time when the effort was to protect the mind through life from any such unbalancing contact. The individual was protected from familiarity with more than one set of opinions--religious, political, social, philosophical, scientific. He was taught facts as facts and no emphasis was placed on the more important fact that there are degrees of certainty and points of view. The next step was to give the individual a free head after the formal processes of education had terminated. Getting out of college was like escaping from a box, where one had been shut up with Presbyterians and Free Traders and Catastrophists and Hegelians--or their opposites, for the contents of all the boxes were not alike. Now, we set the boy free when he enters college and we are beginning to give him a little fresh air in the high school. Why not go back to the beginning? Why not, at any rate, avoid the implication that there is the same backing behind all that we teach or tell? Some teachers, and some parents, have made this plan succeed. One of them is Mr. H.R. Walmsley, who writes in the _Volta Review_ (Washington, April, 1915), on “How I Taught My Boy the Truth.” Says he: I pondered over these things, and determined that I would never tell a falsehood to my child; that I would tell him the truth upon every subject, and that I would not evade or refuse to answer any question. I kept my resolution and have obtained most excellent results. The child doubted nothing I told him. He knew that as far as I was able I would reply truthfully to any question he might care to ask. In answering him I was always careful to qualify my statements thus: “This is so,” “I believe so,” “It is believed to be,” “It is claimed to be,” “Those who should know say,” etc. So he knew the basis from which I spoke. Throughout his life, when he was told anything that looked doubtful, he would say, “I will ask father.”