On the top of this shaft is placed a bevel-wheel, which is geared into by a bevel pinion fixed at the outer end of a short horizontal shaft which passes through the girder, and is furnished with a crank-handle on the inner side.

The arrangement for locking the bridge in its position when shut, and for supporting the ends of the girders, is shown in Figs. 3 & 4. As will be seen from these figures, each girder has bolted to it at each end a casting containing a brass nut in which the vertical screw works. The spindle of each of these screws is furnished at its upper end with a cross handle, and its lower end, which is shaped as shown in Fig. 4, bears in a recessed casting secured to the pier.