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This column continues to provide excerpts from the “Lighthouse Service Bulletin,” a monthly publication of the Bureau of Lighthouses, U.S. Department of Commerce. The first was issued in January 1912, and it continued throughout the existence of the Bureau. Unedited quotes from Volume IV No. 54, dated June 1, 1934, follow. The Bulletin had as its object “supplying information that will be immediately useful in maintaining or improving the standards of the Lighthouse Service, and of keeping the personnel advised of the progress of work and matters of general interest in the service and in lighthouse work in general.”
Important Use of Quick Flashing Lights To Mark Turns – In order to more clearly distinguish the turns and bends of the Delaware River below Philadelphia, the lighted buoys marking the inner sides of these turns will be changed on February 2 to show quick-flashing lights. These quick-flashing lights will have about 75 flashes per minute, a distinctive signal quite different from that used on buoys serving to mark the sides of the channel in the straight reaches. The distinction will be quite apparent by simple inspection without timing, as after the changes are made the other lighted buoys in the river, including those marking the channel sides will be limited to a characteristic of not over 30 flashes per minute. Thus, the buoys with quick-flashing lights will mark only the intersections of the reaches of the dredged channels. This important improvement in the marking of the Delaware River should materially facilitate navigation.
Galvanized Wrought Iron Pipe Structure For Minor Lights – Because of the destructive action of marine borers and tropical storms in the seventh lighthouse district, it was found necessary to design a structure more durable than the old wood ones, and one that was not too expensive, for minor lights in protected waterways. Wooden structures in sand or mud have been destroyed by storms because of the wave impact on the broad surfaces of the piles and the wooden diagonal braces near to the water level. Piles will not withstand the inroads of marine borers, even those that are creosoted failing to last more than about 18 years. Wood piles have the added disadvantage that they cannot be driven deep enough into coral or sand bottoms to withstand tropical storms. An inexpensive structure for minor lights, of wrought iron with cast-iron connecting members has been designed and is suitable for use at submarine sites with either sand or rock foundation, in protected waterways in depths up to 17 feet. This structure is a triangular, pyramidal, skeleton with iron tank house on pipe piles and is 28 feet high. The piles, columns, and struts are of double extra-strong wrought iron pipe. At present there are two of these structures in the Miami main channel. Two more are to be installed soon.
Five Finger Light Station, Alaska, Destroyed By Fire – Five Finger Light Station in Alaska was destroyed by fire on December 8. This station, a combination dwelling and light tower constructed of wood, was built in 1902. At the time of the fire, the lighthouse tender Cedar was off the station landing supplies. The crew of the tender and the light keepers were able to save the boathouse and the carpenter shop, but the tower and dwelling and the radio-beacon building were destroyed. A temporary unwatched light has been established, but the radio-beacon and fog signal will remain out of commission because of the impracticability of beginning reconstruction work during the winter.
Fifth Lighthouse District Completes Electrification of All Primary Seacoast Lighthouses
With the recent electrification of Cape Charles and Hog Island Light Stations, Va., a complete electrification of all primary seacoast lighthouses within the fifth district has been accomplished. The last two installations are of interest as involving lenses of different types, and new motor-driven devices of somewhat different design. The lens at Cape Charles was installed about 40 years ago after having been exhibited at the Chicago World’s Fair, and marked a radical departure in the construction of lighthouse optical apparatus of the first order. The lens and base were mounted on a vertical shaft supported by a mercury float on the lantern floor. As originally installed, the incandescent oil-vapor lamp and the oil tanks all revolved with the lens. The lens clock was mounted on the lantern floor, and revolved the lens by means of a horizontal shaft and a bevel and spur gear connection to the lens mount. In electrifying the lens, this horizontal shaft was extended and an additional spur gear fitted. Through this gear the lens may now be driven by either of two electric motors. Speed reducers are fitted between the motors and the spur gears and each driving unit is protected by sentinel breakers and clutches on the motor-drive pinion. This equipment, on tests and during the first few weeks of operation, has performed satisfactorily. At Hog Island the eight-panel flashing lens is of an old type originally mounted on chariot wheels. The wheels were removed about 15 years ago and replaced by a ball bearing which has since given satisfactory service. This lens was originally driven by a clock through a pinion which meshed with a gear on the lens mount. In electrifying the lens, a brass plate was attached to the lens immediately under the ball race, being secured by brackets to the lens column. On this plate are mounted two 1/12 horsepower electric motors and a double perpendicular speed reducer. The lens makes one complete revolution every six minutes. At both stations, the old lens clocks have been left in place, and can if necessary be placed in service immediately. Both of these stations are equipped with two shunt-wound generator sets and storage batteries and all necessary equipment for lighting the tower, driving the lens, and lighting the keeper’s quarters. Alarm signals are also provided.
This story appeared in the
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