CUTTAGE. =Cuttage.=--The practice or process of multiplying plants by means of cuttings, or the state or condition of being thus propagated. =Cutting.=--A severed portion of a plant, inserted in soil or water with the intention that it shall grow; a slip. Cuttings, particularly of growing parts, demand a moist and uniform atmosphere, a porous soil and sometimes bottom heat. [Illustration: Fig. 30. Hand-glass.] [Illustration: Fig. 31. Small Propagating-box.] [Illustration: Fig. 32. Propagating-box.] =Devices for Regulating Moisture and Heat.=--In order to secure a uniform and moist atmosphere, various propagating-frames are devised. Whatever its construction, the frame should be sufficiently tight to confine the air closely, it should admit light, and allow of ventilation. The simplest form of propagating-frame is a pot or box covered with a pane of glass. To admit of ventilation the glass is tilted at intervals, or two panes may be used and a space be allowed to remain between them. A common bell-glass or bell-jar (_cloche_ of the French) makes one of the best and handiest propagating-frames because it admits light upon all sides and is convenient to handle. These are in universal use for all difficult and rare subjects which are not propagated in large numbers. A hand-glass or hand-light (Fig. 30) answers the same purpose and accommodates a larger number of plants. A useful propagating-box for the window garden or amateur conservatory is shown in Fig. 31. A box two or three inches high is secured, and inside this a zinc or galvanized iron tray, _a_, is set, leaving sufficient space between it and the box to admit a pane of glass upon every side. These panes form the four sides of the box, and one or two panes are laid across the top. The metal tray holds the soil and allows no water to drip upon the floor. One of the best boxes for general purposes is made in the form of a simple board box without top or bottom, and fifteen or eighteen inches high, the top being covered with two sashes, one of which raises upon a hinge (Fig. 32). Four by three feet is a convenient size. An ordinary light hot-bed frame is sometimes constructed upon the bench of a greenhouse and covered with common hot-bed sash. Propagating houses are sometimes built with permanent propagating-frames of this character throughout their length. [Illustration: Fig. 33. Simple Propagating-oven.] [Illustration: Fig. 34. Propagating-oven.]