Four steps are necessary to be followed in this method. The first is securing the animal. The cow is usually kept on her feet, pressed firmly against a wall, the legs secured with hobbles, and her head controlled, as much as possible, by a strong assistant. The second step is the incision of the flank. This is made on the left side, with a sharp, convex bistoury, in the middle of the superior portion of that region, dividing the skin and muscles vertically, care being taken that the incision is not carried too low down, in order to avoid the division of the circumflex artery, which passes along in that vicinity. An opening is then made in the peritoneum, either with the knife or with the fingers, sufficiently large to permit the introduction of the fingers. In the third step of the operation, which comprehends the removal of the ovary, the surgeon introduces his hand into the abdomen, and turning it towards the pelvis, feels for the horns of the uterus. Upon finding these the ovaries are easily discovered. He carefully draws them outwards, and their removal is effected either with the ecraseur or the forceps of Charlier. The operation is concluded by the application of a quill suture. [Illustration: FIG. 29.--CHARLIER’S VAGINAL SPECULUM. (Closed.) (Open.)] [Illustration: FIG. 30. MODIFIED VAGINAL SPECULUM.] [Illustration: FIG. 31. BISTOURY CACHÉ.] [Illustration: FIG. 32. COLIN’S BISTOURY CACHÉ.] CHARLIER’S METHOD--INSTRUMENTS. For this operation special instruments are required. These consist of, first, a vaginal dilator (Fig. 29), or speculum, of peculiar and somewhat complicated construction, to be modified subsequently by another (Fig 30), of superior form and easier of application, and now in general use; second, a bistoury caché (Fig. 31), sliding on its handles, which is a true embryotomy knife, modified by Colin (Fig. 32); third, a pair of long, sharp scissors (Fig. 33), with guarded blades, curved on its flat surface; fourth, a torsion forceps (Fig. 34), closed by a peculiar thread arrangement, moved by the handle; and fifth, a steel thimble (Fig. 35), which has been modified by the instrument shown in Fig. 36, and which is used in applying the limited torsion on the broad ligaments. [Illustration: FIG. 33. SCISSORS TO DIVIDE THE BROAD LIGAMENT.] [Illustration: FIG. 34. FORCEPS FOR CASTRATION OF COWS.] [Illustration: FIG. 35.--THIMBLE FOR CASTRATION.] [Illustration: FIG. 36.--COLIN’S NIPPERS, to take the place of the thimble.]