of which have points of their own. The card system is a series of catalogue entries on single cards, which are stored on their edges in drawers or trays, and kept in order by various mechanical devices, such as rods, blocks, guides, etc. Additions can be made at any point, and the catalogue can be extended indefinitely on the principle of vertical expansion. The drawers or trays are usually kept in cabinets, and with complete sets of alphabetical or other guides, usually cost about 20s. per 1,000 entries. The sheaf system is a catalogue in book form, with single leaves capable of being moved about as required by means of adjustable screw bindings and other devices. These sheaves are usually placed on a shelf, and as each comprises a small division of the alphabet or classification as the case may be, they are easily handled, and hold considerably more than a card catalogue, because both sides of the leaves can be used, and the leaves are much larger than the cards. The cost varies from about 8s. 6d. to 10s. 6d. per 1,000 entries according to the size. For small libraries the sheaf system is probably the most suitable, both on account of its comparative cheapness and the ease with which the public can use it. It is also by far the best form for private libraries, and as it possesses unlimited powers of expansion, it is a library machine of great importance and utility. It is estimated that card catalogues cost about 1d. per 4 entries, while sheaf catalogues cost 1d. for 12 entries, or if both sides of the slips are used, 1d. for 24 entries.
