Below the Keystone Bridge – Part One

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ABOVE: 1872 E.G. Rollins Stereoview of the Great Arch. With the completion of the tunnel from the quarry to Flat Ledge, and the bridge’s completion permitting street traffic through to Pigeon Cove, the process of quarrying accelerated. In the photo above we see the ox cart tracks and a stiff leg derrick to the rear center. Atop, the road level provides a bird’s eye view of work in the quarry. Three silhouetted figures stand akimbo, at the center of the bridge, peering into the quarry. One pedestrian scurries by.
It would be several years before the Rockport Granite Company made the decision to add a railroad system to this quarry system.  [commentary by Leslie Bartlett]
“It took four years to tunnel through the solid rock, drilling and blasting it away, moving the fragments and large pieces as they were loosened. In September 1871 the tunnel was so far advanced toward the highway that a fence had to be put up blocking off half the street.

Foot by foot the workmen progressed, and in the spring of 1872 the roadway was turned more to the west side, for the old roadbed was to be cut away. By July the workmen were blasting out the face of each wall twenty feet below the surface to make a niche for the abutment of the arch. The work was being done under the supervision of Jonathan Pratt of Quincy, said to be an expert on stone arches and bridge building. He told the men the bridge was one of the largest in the state.

The first part of August the men began to erect the arched bridge over the sixty-five-foot span, bank to bank. By September the huge trusses were in position to hold the arch, and the courses of heavy blocks for the arch were creeping up each end as they were set. They would be joined in the center with the final block, the keystone, on each side of the arch. The eastern side was inscribed with the date 1872. On Saturday, September 29, 1872, the keystones were set in and the bridge became a solid arch capable of supporting itself for all time, although it still had its timbers in place.

It was the fastest construction anyone had ever witnessed, for the bridge alone had taken only eleven weeks to complete. The building of the bridge was not without a death by accident. In the spring of 1871, the huge shears used for hoisting rocks and clearing the channel to the tunnel came down with a mighty crash. One of the giant timbers fell on a workman named Peter Rogers, and he was so badly injured that he died that same evening.”
Barbara Erkkila, Hammers on Stone, pp.136

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