Step 2. The plaster is then prepared by shaking the powder into cold water, till a thick cream without lumps is formed; this is secured by constantly stirring the water as the plaster is shaken in. The cream is then poured into the trough, little by little, that it may make its way into the inequalities and recesses under the limb, until the limb is half immersed, leaving the projecting parts, such as joints, half exposed, so that the halves of the mould may separate opposite them. This first instalment is then allowed to set, and a fresh supply of plaster is prepared. Step 3. The surface of the hardened mould is oiled, that the fresh cream may not stick to it, and the whole of the limb is then covered by pouring the cream on a second time. Plenty of plaster should be laid over the projecting parts that the mould may be strong enough for use. It should be ¾ inch thick everywhere, and 1 inch thick along the sides. When the second half is set, the trough or shell is cleared away, and the two halves of the mould removed from the limb separately. For casting, the mould is well oiled inside and filled with cream, which sets into the cast required. While the plaster is liquid, the mould should be well shaken, that the air-bubbles may be all driven from the surface of the cast. CHAPTER V. MISCELLANEOUS. =Hair Suture.=—This is useful to bring the margins of small scalp wounds together, where plasters are not employed. It consists in taking a lock of hair ½ or ¾ of an inch on each side of the wound, and tying them together over a double thickness of lint; by this means the margins of the wound are kept together, and the dressing in place. The slits left after the removal of small sebaceous tumours are very conveniently treated in this way. [Illustration: Fig 70.—Eye Douche.] =The Eye Douche= is a small elastic bottle fitted with a nozzle and flexible tube, ending in a rose, through which, by means of a valve, the water is drawn from a vessel and driven in a fine spray over the eye held open to receive it (see fig. 70). The syringe in fig. 70 is very useful for a variety of purposes. =Eye-Drops.=—Little bottles are sold by chemists for this purpose, with a tubular stopper; at one end of the stopper is a fine jet, the other is closed by a piece of indian rubber stretched over it; on pressing this a drop escapes from the jet. In dropping astringents into the eye the patient should put his head well back; while the surgeon raises one lid from the eye, drops in the lotion, and then raises the other and drops it in again, and tells the patient to move his eyelids about a little to force the lotion over the whole conjunctiva. [Illustration: Fig. 71.—Syringe for sending a continuous current into the nose or ear, &c.]