the end panels at Ashtabula. Thus, the bridge's entire structure relied on just 12 beams and posts (three at each end). Design of the angle blocks Gasparini and Fields claim that the exact design of the angle blocks and the ends (the "bearings") of the diagonals are lost to history. Civil engineer Charles MacDonald, who inspected the bridge's original plans in 1877, described and made drawings of part of the angle blocks. He noted that the vertical posts were made of iron pipe in diameter with a wall thick. Inside the pipe ran an iron rod thick. The top of the rod passed through the space between the members of the chord at the top of the bridge and then through a gib-plate. A nut and washer screwed onto the upper end of the rod, creating tension as well as securing the gib-plate in place. Those angle blocks at the top of the bridge had vertical, squarish lugs. Those members of the chord which ended atop an angle block had their bearings placed against the lug. These lugs served to transmit stress from the chord to the angle block and thence to the diagonals. These upper angle blocks also had lugs facing inward, to which were attached (by means MacDonald did not describe) the lateral braces. The interior side of each upper angle block also had a recess to accept a lug and a tap bolt. The tap bolt was used to connect the lug on the end of the sway rod to the angle block. MacDonald described (but did not publish a drawing of) the angle blocks at the bottom of the bridge. The bottom of the rod in the vertical posts screwed into these angle blocks. The members of the chord at the bottom of the bridge were flat bars, not I-beams, each bar measuring . Where a member of the chord ended at an angle block, a lug was forged at the base of the bar. This lug fit into a slot in the angle block. The angle blocks which made up the chord at the bottom of the bridge also had lugs facing inward, to which were attached (by means MacDonald did not describe) the lateral braces. MacDonald and Gasparini and Fields noted that the diagonal I-beams were designed to connect to both the upper and lower angle blocks with the flanges of the I-beam in