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Re: Baffled by Baffin
From: tony
Date: 2005 Nov 29, 12:00 +0000
From: tony
Date: 2005 Nov 29, 12:00 +0000
Dear Herbert. Thanks for your helpful information. You may have helped us to solved this part of the mystery. Baffin states that Origanus based his tables on Wittenberg but later mentions a 17 degree difference between London and the place where the tables are based. To save your plodding through the thread - the main problem is as follows: Baffin based his original longitude on an 8 minute difference in the hour angle between the sun and the moon at his location and the sun and the moon at London. The moon's retardation that day was about 48 minutes so Baffin concluded that he was one sixth of the way around the earth from London - 60 degrees West. Unfortunately, the 8 minutes difference he obtained was larger than the earlier one at London. A larger hour angle would only have occurred prior to the moon crossing the meridian at London This means that the 60? degrees longitude which Baffin embraced was actually to the east of London and not to the west; a longitude which placed him safely at anchor in the Ural Mountains. > tony wrote: > >> 3. David Origamus was the author of an ephemeris for the years 1595 until >> 1650 and based on the meridian at Wittenberg. Later in his journal, Baffin >> uses both Origamus and Searle with similar results and refers to a 17 >> degrees difference in longitude between London and Wittenberg. >> >> > > Dear Tony, > > I have not yet had a chance to look into the details of your interesting > question which started this thread. But regarding the ephemerides of > David Origanus (spelling! Latinized form of Trost), they are based on > the meridian of Frankurt/Oder. There is no connection between Origanus > and Wittenberg, except, perhaps, that his ephemerides are partly based > on the tables of Reinhold, who taught there. But Reinhold's tables were > based on the meridian of Koenigsberg, Prussia. Origanus was a professor > in Frankfurt when he published his ephemerides, but prior to that he was > in Breslau. Curiously enough, that place is 17 deg east of London. I > leave it to you what you want to make of this. I believe it is just a > coincidence. > > Herbert Prinz