Not only is it necessary for the cataloger to know the material which is in the library itself, but if efficient work is to be accomplished it is decidedly necessary that material not within the four walls should be made available. Let all kinds of knowledge be at the cataloger's command, and make the mechanical devices carry as much of this burden as possible. First of all, material which is in town but which is not contained within your own library, should be noted. Statutes and session laws of all the states should be obtainable though not necessarily a part of the library itself. If a state or law library is near at hand, it is far better to rely upon them as a source of reference than to duplicate such a collection on your own shelves. Articles in law magazines, reports large in bulk, but issued only occasionally, may be noted, when not placed upon the shelves. In Wisconsin we make a distinction between material in existence within the city and that which is in existence elsewhere, such as in the Library of Congress, the John Crerar library, or nearby institutions. A manila catalog card tells us that the material may be found outside of the city, whereas by stamping the name of the library in the place of the call number on a white card, we indicate that the material is in town. Subject entries only are made for material of this sort. There are many indexes already in existence which will supplement the catalog and call to the attention of the worker available material. One of the most valuable sources of all is found in the experts of the neighborhood. The librarian is too prone to think that all the most useful knowledge is in books or printed form. Some of the best help imaginable can be obtained from men. Every community has within its borders specialists of various types; men who have given their lifetime to the study of some particular question. Make such individuals a portion of the catalog; use them as sources. The telephone is at your command and oftentimes more valuable information can be obtained from some person within telephone call than can be gotten from hours of work with shelf material. Furthermore, do not limit yourself to the talented man within the community, but use the expert wherever he may be found. Correspondence will often bring information to your door; mount the letters; put them with the clippings or catalog them separately; in case of urgency, telegraph. In fact, have some of the appropriation deliberately set aside for supplementing the catalog by telegrams.