1874:	The light was first shown at Spectacle Reef Lighthouse, located on a limestone reef at the northern end of Lake Huron, near the Straits of Mackinac, ten miles from land.  The structure of this lighthouse was similar to that of Minots Ledge, and its construction was "a notable engineering work."
1941:	South Greenland Patrol organized with 3 cutters and a Navy vessel.