114 THE KANSAS CITY BRIDGE.

The calculations of the contractors, by which the draw was framed, were
made on the supposition that each arm acts as an isolated truss when the draw
is closed ; the panel ties are therefore of the same size at the centre and ends
of the draw. To make the actual strains agree with these calculations, the
lifting jacks placed under the end posts must carry one-half the weight when
the draw is fully loaded, the weight carried by each jack being

91 2080 = 189,280 pounds.

The weight carried by each end bearing, under the present arrangement of
wedge plates, is

(182 — 145.25) & 2080 = 76,440 pounds.
making the weight which would actually be lifted by the jacks under each
post, after closing the draw, 112,840 pounds.