To make a secure fastening they
were notched together and strengthened with diagonal braces. Each king
post was notched on opposite sides, at about thirty inches from the top. A
temporary tie piece was also nailed across the lower ends of the king
posts. The frame thus formed was set up at the center of the span and
temporarily held by nailing the lower tie piece to the working platform.
Four stout spars were now cut, each about fifteen feet long. Taking a pair
at a time, we planted their lower ends firmly in the opposite banks and
sawed off their upper ends until they could just be hammered into the
notches in the king post. This required careful fitting, but by making the
spars a little too long to start with, and then shaving them down with a
draw-knife, we managed to make fairly good joints. A couple of long wire
nails in each spar made the structure perfectly secure. The king posts
were now sawed off just above the temporary tie piece, and the permanent
cross beam was fastened to these ends with straps of heavy wire wound
tightly about them. The working platform sagged so much that we were able
to lay this cross beam above it. From the ends of the cross beam diagonal
braces extended to the king posts (Fig.
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