Bridge proposals include correspondence, notes, drawings, specifications and estimates made by Washington A. Roebling. The proposals include several military bridges designed by Roebling during the Civil War, consultations on and histories of bridges built by John A. Roebling, and the Hudson River Bridge which Roebling endorsed.

Bridge proposals consist of correspondence, notes, drawings, specifications and estimates made by John A. Roebling. Of particular interest in this series is the Kentucky River Bridge which Roebling started but did not complete, the Tripartite Bridge, a creative solution to bridging the three rivers of Pittsburgh, and the St. Louis River Bridge proposal which was turned down in favor of James Eads’s design.