Papa-Bear-NYC Posted August 20, 2009 Share Posted August 20, 2009 (edited) I recently spent nearly a week in eastern and northern Maine around the first of August doing some serious survey marker hunting. My searches were centered around 1) the Eastern Oblique Arc and 2) the US-Canada boundary with a few triangulation stations thrown in. It involves stations up in Aroostook and Washington counties which are a looooong way away and where things are faaaaar apart. I drove over 1200 miles in 5 travel days! My interest in the Eastern Oblique Arc (EOA for short) is familiar to many in this group. This is the 6th forum thread on the subject. Check these links for the past threads. My vacation intersects the Eastern Oblique Arc October 2007 The Eastern Oblique Arc crosses Massachusetts April 2008 The Eastern Oblique Arc meets the Borden Survey July 2008 The Eastern Oblique Arc in Western Maine and New Hampshire August 2008 The Epping Base Net of the Eastern Oblique Arc November 2008 I got intrested in the EOA in the summer of 2007, as I was planning a trip to Maine and New Brunswick as a vacation with my wife. Prompted by some discussions on this forum, I had recently read Holograph's excellent Wiki on the Eastern Oblique Arc. This described the monumental project done by the Coast Survey from about 1830 to about 1900 which surveyed the entire East Coast to an unprecedented level of accuracy. And in so doing, helped establish the "Figure of the Earth" (the exact shape of the earth's spheroid in North America) which laid the foundations of modern datums. Pretty great stuff, of which I was totally ignorant until then. So my 2007 trip was devoted to finding as many stations as possible that still exist in the area. Here's Holograph's Wiki: EOA Wiki. This years trip was built on two basic ideas: finish the missing stations in the easternmost segment of the EOA, and check out the connections made in the 19th century between the primary triangulation scheme (the EOA) and the US-Canadian boundary, which after nearly 50 years of wrangling, was finally agreed upon in 1842 and laid out in the several years following. As for the EOA, check out this map: Here's the link to the live interactive version: EOA Easternmost section Move it, zoom it, click on the stations, explore the area. Rye 1866, in the upper left of the triangulation scheme was the last one in Maine that was known still to exist, and one for which I had a DNF in 2007. I'm happy to say that push pin was turned green in this trip and I have a note below in this thread on that happy find. Besides the gray push pins on Howard (under a concrete radar pad) and Grand Manan Island (a very long swim) I was finished with this section. But what about the three red ones: St. David, Calais Observatory and Prince Regent Redoubt? Well, St. David was lost when the owner of the land "removed the station-mark and built a house over it" in 1887 (quote from 1888 CGS Annual Report), and Prince Regent Redoubt was lost in 1910. Not much to go on there. But Calais Observatory was another story. The logs on the datasheet say it was lost prior to 1935, and a 1998 log said the stone the transit was mounted on was found at the foot of the hill, so I figured that was that. But when I visited the site in 2007 anyway, I was intrigued by a new NGS disk that had been placed there a few years prior, and that story went on as I learned more about the history of the site and this culminated on August 4th. See the note below on this highly unusual story. As for the connection with the boundary, I found these two excerpts from the CGS annual reports: From the 1867 report: And from the 1890 report: So I visited a couple of the stations in question and you will hear about that in another note below. Finally there were two triangulation station unrelated to these topics, but which were nice finds nevertheless, plus a few more reference monuments in the Calais Area which were set by the boundary commission when the route of the boundary through the St. Croix River was fixed in the early part of the 20th century. Read on ... Edited August 21, 2009 by Papa-Bear-NYC Quote Link to comment
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