=Importance of Reference Work.=—The average reader is uninformed as to the use and helpfulness of any but the commonest reference books. The duty of instructing the readers in the use of the ordinary library tools devolves upon the assistants at the reference desk. They must interpret the catalog to the public and incite in the readers a desire to help themselves after they have been initiated into the use of a dictionary card catalog and have had the use of some of the more important reference books explained to them. If an education consists not so much in getting knowledge as in knowing how and where to get it when the need arises, then it is clear that the assistants at the reference desk fill an important place in the library staff. They have a great opportunity for helpfulness. Other divisions of the library may labor successfully to build up the collections, and have them properly classified and cataloged, but if the service at the reference desk is inefficient the usefulness of the library is sadly impaired. The reference assistants can make or mar the library’s reputation for service. Of course there is such a thing as doing too much for the patrons of a library, thereby preventing their learning how to help themselves. Let the readers understand that it is necessary to dig into the contents of the books and discover things that the bibliographies and card catalogs cannot point out. Don’t say off hand, “I don’t know that we have anything on the subject,” for fear that before long you will be saying categorically that “The library has nothing on the subject.” You should aid the inquirer by beginning the search. Say rather, “Let us see what the library has on the subject.” When the books are purchased and on the shelves, and the catalog is in perfect shape for use, the library is still a riddle to the public. There must be one or more capable persons to meet the public and put the contents of the library at its disposal. “Knowledge is of two kinds,” said Dr. Johnson. “We know our subject and we know where we can find information upon it.” The latter is the knowledge necessary to the reference librarian. Her knowledge of her library must be such that she can find something about any question asked, if there is material on the subject in the library. What great novel is there on the period of the Norman conquest? Where can I find a map of the city of Seattle? Who was the last man elected to the French Academy? What is the point of resemblance between Maeterlinck’s writings and Coleridge’s Ancient Mariner? Was Rabbi Ben Ezra a mathematician? Such are the questions for which she must be ready, from morning till night, to help find the answers.