The Scientific American Boy Part 24

REDDY'S CANTILEVER BRIDGE.

I believe I have given a careful account of everything that was recorded in the chronicles of the society. We were too discouraged to undertake anything new in the two weeks before school opened. I presume I might mention here Reddy's cantilever bridge, which, however, had really nothing to do with the S. S. I. E. E. of W. C. I., because our society was formally disbanded the day before Bill and I returned to school.

About a month after leaving home I received a letter from Reddy inclosing three interesting photographs, which are reproduced herewith.

Reddy certainly had the bridge fever, because soon after we had left he started to work, with the rest of the boys, on a cantilever bridge across Cedar Brook. The brook was entirely unsuited to such a structure, because the banks were very low; but he made the towers quite short and built an inclined roadway leading up to the top of them. The legs of the towers were driven firmly into the bank, making them so solid that he thought it would be perfectly safe to build the frames out over the brook without building them at the same time on the sh.o.r.e side. But he had made a miscalculation, for when a couple of the boys had crawled out on the _B_ and _C_ frames to set up an _E_ frame the structure commenced to sag. The trouble was remedied by propping up the tower with a stout stick driven into the river bottom and wedged under the upper tie piece of the tower. The towers were really too short to make a well proportioned bridge, for the panels had to be made very long and narrow, so as to reach across. But on the whole it was a very creditable structure when completed, though it had only half as long a span as our cantilever bridge over the lagoon.