The 141st Meridian: A Single Straight Line
The 141st Meridian was not included in the 1904 agreement to mark the boundary in the Alaska Panhandle. Two years later, on 21 April 1906, it was covered in a convention between Great Britain and United States. 1 Under it, the position of the 141st Meridian would be determined at a single point, using the telegraphic method, and this line would be projected north to the Arctic Ocean and south to the flank of Mount St. Elias, overlooking the Pacific Ocean. Once again, King and Tittmann were designated commissioners for the project.
Using telegraphic methods, far greater accuracy would be possible than with the astronomic methods used by Ogilvie and McGrath. The commissioners selected Boundary, on the south bank of the Yukon River about three miles west of Ogilvie's observatory, as the site for the longitude determination. From it, there were telegraph connections to Vancouver, B.C., via Dawson, and to Seattle, via Eagle and a cable from Valdez. Some work had already been done; in 1905 the longitude of both Vancouver and Eagle (Fort Egbert) had been tied to a station in Seattle. Now, the difference in longitude would be determined between three stations, Boundary, Eagle, and Vancouver. Calculation of the results would take time, and if surveys were to go ahead in the 1907 season it would be necessary to start the work in 1906 without waiting for formal ratification of the convention. On 19 August 1906, just three days after formal ratification, F. A. McDiarmid, of the Dominion Observatory in Ottawa, began observations at the Boundary site. 2 His astronomical transit was installed on a cement pier, located about 20 feet south of the river and 352 feet to the east of Ogilvie's line of 1895-96.