Re: Monday answer
Gary gets the gold star for his forehead. May it serve as a beacon to keep him from floundering. Today�s answer is one of America�s most beloved building types -- the lighthouse.
The archaeological excavation is being done outside of Alexandria, Egypt, and that is the Pharos lighthouse (270 BC), one of the seven wonders of the ancient world. Around the Mediterranean the Arabs, Moors, and the Romans used lighthouses and developed polished reflectors to increase the light output and direction of beam. Finding fuel and transportation for it to remote sites was a high maintenance item for almost all lighthouses up until electricity. Alas, most of old technology was lost in the Dark Ages. Surprising to me, Finland and Denmark were among the early users of lighthouses. Flash forward a few millenia. George Washington, as President, personally approved the funding, location, and keepers of early lighthouses.
John�s early guess as a measuring device and my hint with the �department in any library� was as a �reference�. The measurement factor was from the lighthouse to hazards like rocks, or bars. It also gave the reference angle to a point of land. The movement in the trivia was not as a marking device per se, but the rotation and frequency of the beacon �flash�. With the correct chart and a pelorus, speed and direction of a ship with reference to land could be estimated. Sighting the light could in the best of circumstances and a first order light could allow a ship to stay twenty or more miles offshore.
The greatest invention for lighthouses was the Fresnel lens which is a remarkable story if you are interested in the science of optics. But for this trivia it is only well to know that a bureaucrat, an auditor, Stephen Pleasonton, in Washington, DC who was supporting his friend (a Winslow Lewis), refused to put the lenses in American lighthouses for forty (40) years because he was a tight fisted numbers guy, and didn�t understand the need or science. He relied on his friend (who owned the existing franchise for lights) to tell him if Fresnel lenses were a better technology and, of course, the answer was �no�. It took death to get America back on track with Fresnel lenses which cost $15,000 (1840 dollars) plus shipping from France. A legitimate 1st order Fresnel lens today is valued in the 2 millon dollar range. Replacement glass prisms for any light are almost impossible to replace. Plexiglas replacements often appear with the real prisms in museum displays.
Of those lighthouses still in existence, and there are about 160 around in the U.S. and many more around the world, there are six (seven if you count a replica) that are of wood. Of these, four are part of the light keeper�s house. Indicated by a (*). Typically they are clapboard or shake built into the center of the house, rising two floors above the residential area and not a separate tower. If these buildings would be located elsewhere they might be taken as a Midwest fire station with a built in hose tower.
(*) Rose Island Light in Newport, Rhode Island, -- owned by a private Foundation
(*) Pomham Rocks Light, East Providence, Rhode Island -- deactivated 1974 but restoration underway through 2006. Now a permanently lit private aid to navigation.
(*) Hereford Inlet Light, North Wildwood, N.J., -- moved inland and now a private aid to navigation.
(*) Old Yaquina Bay Light, Newport, Oregon, private aid to navigation, with a keeper for the protection of the old light. Now part of a state park.
Mukilteo Light, Mukilteo, Washington, -- Small wooden clad tower, part of private foundation, and the city of Mukilteo.
Mystic Seaport Light, Mystic, Connecticut, -- a wood shake replica two miles upriver from Noank, Connecticut, and a copy of the Brant Point Light on Nantucket Island Massachusetts �still in operation with a red light.
Lighthouses are now mostly classified as aids to navigation but not essential owing to modern GPS, Doppler radar, and sonar.
Lots of information and references. There is a web page or more on most of the existing lights. The Fresnel lens is a good story. So are the stories and schedules of the light keepers�every three hours, 24/7, to either wind the rotating mechanism, replace the lamp wicks, or the oil, or stoke the furnace for steam to run the fog horn. In addition every so often they lugged up their tower heavy containers of mercury on which the rotating beacon floated in a low friction bath. These men and women were dedicated!
Finally, as an adjunct, Northern Shipwrecks Database... Over the last 26 years, Northern Maritime Research has accumulated a database of more than 100,000 North American shipwrecks the lighthouses didn�t save covering 400 years. There is a list of wreck totals off the shores of the coastal states and descriptions can be had on each find...
Assorted facts about light houses
*Oldest existing is in Spain
*Oldest in the U.S, Sandy Hook, N.J.
* Most light houses in a state�Michigan, 220
* Most expensive St. George Reef, California, $715,000 (1882-1892)
*Light House mandated by law to be at all times manned and turned on and off by hand-- Boston Harbor
*The fog horn beeeeeeeohhhhhh sound is called a diaphone. The steady brrrrrrrrrrr sound is called a diaphragm.
* Before electricity and banks of batteries, whale oil with its clean burning was the first fuel, followed by cabbage oil, then lard, then kerosene.
* Ben Franklin said they were more important than churches.
* Glazing on lighthouse towers is called storm panes
* Keepers were paid the equivalent of todays $16,000 a year (considered lower middle class at that time)
* The Scottish family of Robert Louis Stevenson, (Treasure Island, Kidnapped, Dr. Jekyll and Mr. Hyde) for 80 years was the family specializing in building light houses. They were all engineers except for him, and did their work in Europe and the Far East.
* Before the ignore gender Coast Guard took over responsibility, there were 80 female keepers on record for the U.S. Lighthouse Establishment.