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Longitude by Wire


holograph

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I just finished reading the book "Longitude by Wire, Finding North America" by Richard Stachurski, 2009, University of South Carolina Press.

 

It gives an account of the early days of the Coast Survey, when Hassler and Bache were first setting the standards for scientific surveying. Primarily it is the story of the use of the telegraph to find accurate longitudes, and the laying of the transatlantic cable that finally allowed the Survey to determine the longitude of North America relative to Greenwich.

 

Those of you who are interested in the history of surveying and geodesy in the U.S. may be interested in the book.

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I just finished reading the book "Longitude by Wire, Finding North America" by Richard Stachurski, 2009, University of South Carolina Press.

 

It gives an account of the early days of the Coast Survey, when Hassler and Bache were first setting the standards for scientific surveying. Primarily it is the story of the use of the telegraph to find accurate longitudes, and the laying of the transatlantic cable that finally allowed the Survey to determine the longitude of North America relative to Greenwich.

 

Those of you who are interested in the history of surveying and geodesy in the U.S. may be interested in the book.

A couple of years back, I was privileged to be present at the dedication of "Meridian Park" in Calais Maine. The longitudinal observatory at this site served as the last link or the "Golden Spike" of the telegraphic determinations from Europe to the US from 1855 to 1866.

 

Here's a report I put on this forum (part of a longer thread): The Curious and Wonderful Tale of the Calais Observatory.

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The longitude book looks interesting. I have too much reading stacked up right now to add another, but I'll try to remember to look for it some day.

Amazon link

 

I'm currently reading Linklater's Fabric of America which mostly follows Andrew Ellicott and discusses how the politics of the post-revolutionary period were intertwined with establishing state boundaries to permit taxation and land sales. The book does a lot to take the shine off your image of the founding fathers, who often had what we today would call major conflicts of interest, making fortunes from investments associated with their official decisions.

 

It makes you wonder on one hand how anything got done in the political environment, and on the other how some people accomplished so much.

 

Ellicott favored the determination of longitude by having teams at the points to be compared, who set their chronometers by the eclipses of Jupiter's moons and then made stellar observations. Hundred of observations. The book is light on technical details, giving only a few clues to the accuracy of results. I'd like to see a comparison of the accuracy Ellicott obtained versus what telegraphic time made possible.

Edited by Bill93
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Ellicott favored the determination of longitude by having teams at the points to be compared, who set their chronometers by the eclipses of Jupiter's moons and then made stellar observations. Hundred of observations. The book is light on technical details, giving only a few clues to the accuracy of results. I'd like to see a comparison of the accuracy Ellicott obtained versus what telegraphic time made possible.

 

Stachurski has a 20-page chapter outlining several of the various methods in use at the time: lunar culminations, eclipses of Jupiter's moons, eclipses of the Pleiades, and exchanges of chronometers. He explains a little about each technique and its problems, and why none of them could be as accurate as the telegraphic method.

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Sounds like an interesting read--especially since I was a professional telegrapher for over a decade. The invention of the telegraph ushered in an age of accurate weather forecasting by allowing simultaneous reporting of weather conditions over a wide area. Obviously, it provided increased accuracy in the surveying profession, as well.

 

The photo below shows a plaque at a Longitude Station (EZ5145) on the grounds of the North Carolina Capital building in Raleigh. Click here for lots of photos of the station. Notes in the original description and recoveries indicate that no one responsible for caring for the Capital grounds knew what the large stones were for.

 

-Paul-

 

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When this thread first appeared I put the book on my Amazon wish list. Early this year I got a gift certificate for Amazon so I bought it and put it in the books to read cue.

 

I just finished the book. It is very well written and I really liked the details like how they connected the clocks to the telegraph.

 

Thanks to Holograph for the recommendation.

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I don’t know how much the transit of Venus on June 5th was talked about in the “lower 48” but there was a bit of a buzz here because it was one of the few places that it could be seen from start to finish. It was a great sight to see.

 

But I remembered there was a benchmark with that same name. I found it TU1283.

 

In the publicity about the transit of Venus Bob Sigall a columnist for the Star Advertiser ran a history column on the British party that arrived here to observe the transit of Venus in 1874. They set up in three locations in the islands Kailua-Kona on Hawaii; Waimea Kauai and Honolulu Oahu. The purpose of the expedition was to help determine the length of the astronomical unit.

 

Bob also pointed out the book Hokuloa: The British 1874 Transit of Venus Expedition to Hawai'i by Michael Chauvin. I was able to grab a copy at the library. Odd thing was the book was published in 2004 and I was the first to check it out. I recommend the book. Among the interesting facts is that the expedition brought with them 20 chronometers.

 

In looking at the data sheet for TU1283 I see the 1932 and the 2009 recoveries are of the wrong. Looking at location for TU1283 on Google Earth it looks like the station is gone because it is in a parking structure. But I’ll go look for it and make a found/not found recovery depending on what I find.

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