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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip observations by Carnegie Institution
From: Richard B. Langley
Date: 2013 May 20, 10:08 -0300
From: Richard B. Langley
Date: 2013 May 20, 10:08 -0300
Paper extracted from the "book" and attached. -- Richard Langley On 2013-05-19, at 8:36 PM, Paul Hirose wrote: > > Bowditch (volume 1, 1984) mentions the results of 5000 dip measurements > at sea by the Carnegie Institution. I haven't found the source document, > but in 1918 a Carnegie scientist, Willliam J. Peters, summarized 3031 > dip observations in "Results of Dip-of-Horizon Measurements Made on the > Galilee and Carnegie, 1907-1917." [Terrestrial Magnetism and Atmospheric > Electricity, volume 23, number 2 (June 1918), page 47] > > A scan is online at archive.org: > > http://archive.org/details/journalofgeophys22ameruoft > > To download (not view online), click "HTPPS" in the "View the book" box. > The article begins on page 261 of the document. > > Peters says the visible horizon was never more than 2.4 minutes above or > 2.0 minutes below the geometric horizon. He concludes dip tables that > ignore temperature are sufficiently accurate for navigation. > > -- > > > > : http://fer3.com/arc/m2.aspx?i=124098 > ----------------------------------------------------------------------------- | Richard B. Langley E-mail: lang@unb.ca | | Geodetic Research Laboratory Web: http://www.unb.ca/GGE/ | | Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | | Fredericton? Where's that? See: http://www.fredericton.ca/ | -----------------------------------------------------------------------------
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