The new station's lens was installed and tested in June 1895, however, its full-time service was delayed until mid-August so mariners could be properly informed of the station's new light characteristic. Lt. Frederick Mahan of the Lighthouse Board proposed that all U.S. lighthouses be given a “numerical flash” pattern. The first-order lens at Cape Charles made a complete revolution every thirty seconds, producing nine flashes: four quick flashes followed by a dark interval of three seconds, then five more flashes followed by sixteen seconds of darkness. Cape Charles would thus have a 4-5 pattern, and mariners could easily associate these numbers with Cape Charles. This numbering system was likened to a fire alarm bell stroking out the exact numerical identity of a beleaguered building. “By this method,” Mahan maintained, “the light is identified absolutely…” Due to the high cost of these special lenses, only the “4-5” light at Cape Charles, and the “1-4-3” light at Minots Ledge were ever deployed.
