The
frames on the second tower were now similarly erected and anchored, after
which we were ready to put in the center panels of the bridge.
[Illustration: Fig. 319. Preparing to Put an E Frame in Place.]
The Center Panels of the Bridge.
First, the frame H was wedged into place and thoroughly fastened by a
liberal winding of wire. Next the frames I and J were set in place, and in
order to do this we had to remove the upper tie pieces of these frames.
Then one frame was hooked in the other, and the two were carried out on
the scow under the center of the bridge. Ropes were tied to the ends of
the two frames, and they were lifted together, like a wide V, to the
position shown in Fig. 318, after which the tie pieces were bolted on
again, resting against the ends of the E frames. As an additional
security, two sticks were bolted to the under side of the frame H, one at
each side of the I and J frames. The bridge was then completed by wedging
the frame K under the ends of the D frames, and also placing a stick
across each tower under the joints of the D frames. We planned to run our
gravity railway across this bridge, moving our platform and trestle to the
opposite bank; so instead of flooring our bridge with slabs, we fastened
ties across at intervals of 15 or 18 inches.
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