Fig. 25.
Fig. 26.
Fig. 27.
The part that next claims our consideration is the
armature, with its fittings. The armature is made out of 5/16 square bar iron, of the best quality, soft, and well annealed, and filed up smooth and true. The proportionate length is shown at Figs. [23] and [24]; and the size of the iron for other bells is regulated in the same ratio as that of the cores. Two methods of making and attaching the springs and hammers are shown. [Fig. 24] shows the section of an armature fitted with back spring and contact spring in one piece. This is cut out of hard sheet-brass, as wide as the armature, filed or hammered down to the desired degree of springiness, then filed up true on the edges. It may be attached to the iron of the armature, either by soldering, by rivetting, or by means