Bending steel girders. Washington, D.C., Sept. 23. During the testing of the rigid steel frame knees at the Bureau of Standards the officials were constantly watching the girders to determine the exact moment that the load buckled or weakened the knees. This was done as the huge 600,000 lb. testing machine applied the pressure to the steel knees. 9/23/37
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Harris &amp; Ewing, photographer</div>
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