Figs. 10 and 11
The usual form hitherto has been that shown in figure 10. The cross piece was horizontal and formed simply a posterior semicircle; the lateral steels were straight. Consequently in this pattern these steels form a cone, in which the soft parts are not compressed on the inner side, nor drawn outwards, as in the apparatus previously described. Further, as long as the stump is not shrunken, the ischium covered on its inner side by soft parts sinks into the bucket, and it is the perineum which becomes the point of pressure ([Fig. 11]). Made of leather, the perineal concavity soon loses its shape and really no longer exists. Finally the bucket is circular, with the faults inseparable from that shape ([Fig. 12]).
In cases where it is felt necessary to employ leather, all these faults are easily corrected, by giving the cross piece the shape which we have described for the wooden bucket, and by prolonging it forwards through two-thirds of the corresponding circumference, in the shape of an oblique bucket. (Dotted line in [Fig. 12].)
If it is not strengthened, an oblique border of leather gives way, and after a few months' use allows rotation. The leather which extends from the termination of the metal ascends very steeply towards the trochanter, whilst the posterior border of the bucket, which is horizontal, curves downwards on the inner side to form the perineal concavity.
Figs. 12,13 and 14
The ordinary leather bucket is mounted upon two lateral steels, which are joined by a posterior cross piece (Fig. 13). This framework is shown in [figure 10], and covered with leather in figure 12. If the lateral steels are straight and divergent, this has all the defects of the straight circular bucket. The concavity for the perineum, cut out of the leather, soon loses its shape. It is, however, easy to shape the cross piece as shown in figure 14, with a perineal concavity and the anterior border oblique, following the dotted line in figure 12. By doing this and curving the steel uprights appropriately, the correct form of the wooden bucket can be copied exactly in a leather and steel apparatus. Such a correct apparatus is shown in [figures 15 to 18].
In [figure 14] is seen the metal framework; in figures 15 and 16 that of the apparatus covered with leather; in figure 17 the support upon the ischium; and the possibility of making this appliance identical with the wooden bucket will be observed ([Fig. 18]).
