Resetting capstones on Thirteen Stones

One of the larger projects during my time as an intern for CMCP was the resetting of numerous capstones on a group of thirteen wall sections made of various types of granite, limestone, and marble in Van Cortland Park. These “Stones” were built as a contest for native quarries to win the contract for the building of Grand Central Terminal: 15 wall samples were built to identical specifications and left to weather in the open for a few years to see how they would wear. Today, only 13 of the original 15 remain, and due to their remote location, were subject to many acts of vandalism such as graffiti and the toppling of any loose capstones.

Under our supervisor’s instruction, my cohort and I washed the Stones, treated the graffiti, located the missing capstones in the surrounding area, and matched them to their appropriate structure. Using an improvised stencil, we drilled matching holes into the tops of the structures and the underside of the capstones, hoisted the capstones up with a gantry crane, and reset them in beds of mortar, with epoxied pins holding the capstones securely in place so they could not be pushed off again. Finally, we repointed the joints to give it a clean finish.