The Edgerton Bell is a monumental 700-pound bell cast in 1864 by Henry N. Hooper and Company, a firm begun by Paul Revere. It once rested on the Graves Ledge Bell Boat, which had been set at anchor in 1854 as America's first sound buoy, and it served to warn mariners of danger at the treacherous Graves Ledge about a mile northeast of the mouth of Nantasket Roads where Boston Harbor opens to the ocean. This was the second United States Lighthouse Establishment bell placed on the Graves Ledge Bell Boat, and the fate of the first bell has never been discovered. With this bell aboard, the Bell Boat sank in a storm in 1876 and was replaced by a bell buoy known for its weirdly mournful and blood chilling sounds. Divers recovered the bell in 1963 while Dr. Harold Edgerton of the Massachusetts Institute of Technology was working at the Graves End Lighthouse, and he purchased it and studied its qualities for his work in sonar and underwater discovery. Edgerton's maritime career also included improvements in lighthouse lenses, advancements in underwater strobe photography, and work at times with Jacques Cousteau. The bell was later placed in the chapel on the M.I.T. campus as a donation from Edgerton's widow, and in the spring of 2015 M.I.T. offered it to the Scituate Historical Society. Henry N. Hooper and Company also cast a bell of more than 21,000 pounds for the City of New York, the largest bell ever cast in the United States, and produced the bell found outside the Monhegan Light in Monhegan, Maine, which served at the Manana Fog Signal Station and became the model for Jamie Wyeth's painting Bronze Age.