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Re: Measuring Dip in the 18th Century
From: Brad Morris
Date: 2013 Dec 29, 01:27 -0500
From: Brad Morris
Date: 2013 Dec 29, 01:27 -0500
On Dec 29, 2013 1:26 AM, "Alexandre Eremenko" <eremenko@math.purdue.edu> wrote:
Brad, >http://www.dehilster.info/index.php?>doc=http://www.dehilster.info/instrumenten/davis-quadrant/index.htmlto Unfortunatey, this reference does not work:-( Perhaps I did not make my point clear. Let me try again. We see a dip table made in XVI century. We can easily check it by comparing with modern almanac. It does not show 10' errors, does it? Conclusion: They could measure angles in XVI century with about 1' accuracy. Now I ask: with what device? I conjecture that this was something similar to backstaff. On my opinion, all arguments about GPS and modern obsession with many digits which Frank and you give, are not related to this question. Alex.