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Rh at the corners if frequently handled. The uncut boards should be perfectly flat in order that ruling, printing, and cutting may be executed with accuracy. Guillotine cutting is not so satisfactory as cutting singly with a hand cutter or rotary cutting on a card cutting machine. The usual sizes of index boards are 20½ by 25½ inches and 30½ by 25½ inches, cutting to 5 by 3 inches, 6 by 4 inches and 8 by 5 inches.

Kraft Papers.—"Kraft" means strength, and this is the characteristic of these papers. Unbleached wood pulp is the material used, and by prolonged boiling with soda under comparatively low pressure, the fibres receive less drastic chemical treatment than is usual in the