1887 Map of Agate Bay showing proposed breakwaters.

Two Harbors Lighthouse commenced operation on the eastern side of Agate Bay in 1892, and on December 14, 1895 a white, eight-day lantern light, shown from an iron post at an elevation of thirty feet above lake level, was established on the outer end of the eastern breakwater that extended from the shore near the lighthouse. In 1902, after the work on the breakwaters had been completed the previous November, the iron post was moved 300 feet from the angle of the pier to the outer end of the newly constructed ell, where the light was changed from a lens-lantern to a Pintsch gas light. Compartments were constructed in the breakwater to hold two eight-foot-long, cylindrical gas tanks, which were connected via pipes to the iron post supporting the light. The new gas light was first exhibited on September 10, 1902.

Four years later, the post light was replaced by an enclosed light tower, described in the Annual Report of the Lighthouse Board:

The combined light and fog-bell tower and an electrically operated fog bell, on the easterly breakwater, was completed on August 4, 1906, and on August 4 the light and fog-signal went into operation. The new tower is 33 ½ feet high to the focal plane, and is a square, pyramidal, skeleton iron structure, painted white, surmounted by a square watchroom and black octagonal lantern. The fog bell is hung from the front of the tower and strikes a single blow every 10 seconds.

A frame powerhouse, equipped with an oil engine, dynamo, and switchboard, was built onshore near the fog signal building at Two Harbors Lighthouse to provide power for the fog bell machinery. The weights used to power the striking machinery were wound up by a motor that was connected by wires to the powerhouse. The 1,500-pound bell was manufactured by Gamewell Fire Alarm Co.

The 1906 lighthouse remains in service today, exhibiting a red flash every six seconds. The 1,500-pound fog bell has been replaced by a horn that can be activated by keying a microphone five times on VHF-FM Channel 79.

References

1. Annual Report of the Light-House Board, various years.
2. Report of the Commissioner of Lighthouses, various years.