Spectacle Lighthouse - 1902
Photograph Courtesy National Archives
Spectacle Lighthouse - 1906
Photograph Courtesy U.S. Coast Guard
NAVIGATION - LAKE HURON
"The lighthouse is 11 miles (18 km) east of the Straits
of Mackinac and is located at the northern end of Lake Huron, Michigan. It was
designed and built by Colonel Orlando Metcalfe and Major Godfrey Weitzel and
was the most expensive lighthouse ever built on the Great Lakes. The site was
first marked by a buoy in 1868. The construction was undertaken under the
auspices of the Lighthouse Board, and was a feat of civil engineering and
endurance. Construction began in 1870, in answer to the disastrous loss of a
large number of ships during the 1860s at the site; in particular, two
schooners ran aground and broke up in 1867. The massive cost of the loss helped
convince Congress that it would be more cost effective to build a light and
reduce the potential of future shipwrecks. The lighthouse is built upon a reef
shaped like a pair of eyeglasses (hence its name) and is located in the path of
littoral commerce on Lake Huron. The increase in freighter traffic through the
straits increased the risk of more ship losses without better signing of
hazards. The Spectacle Reef Lighthouse cost $406,000. The tower is formed as a
"frustum of a cone". The 32-foot (9.8 m) diameter base rises 93 feet
(28 m) above water level, and is 11 feet (3.4 m) below water level. As the
Coast Guard notes: "The focal plane is 4 feet 3 inches (1.30 m) above the
top of the parapet, making it 97 feet 3 inches (29.64 m) above the top of the
submerged rock and 86 feet 3 inches (26.29 m) above the surface of the water.
For 34 feet (10 m) up the tower is solid and from them on up it is hollow. In
it are five rooms, one above the other each 14 feet (4.3 m) in diameter, with
varying heights. The walls of the hollow portion are 5 feet 6 inches (1.68 m)
at the bottom, tapering to 16 inches (410 mm) at the spring of the cornice. The
light has an attached fog building, oil house and storage building. There are
davits to raise and lower boats. Original
lens was a Second-order Fresnel lens, current lens is a Solar powered 300 mm
Tideland Signal acrylic lens. Intensity: 400,000 candlepower white; 80,000
candlepower red. Range: 11 nautical miles (20km). Characteristic: Flashing
alternately white every 60 seconds, red every 5 seconds. Operates year round.
100 candlepower white winter light which flashes every 5 seconds. Fog signal:
air-diaphone."
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