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Re: 1491 The year China discovered longitude
From: Philip Bailey
Date: 2004 May 8, 14:02 +0100
From: Philip Bailey
Date: 2004 May 8, 14:02 +0100
On Saturday 08 May 2004 11:07 am, Antonio Canas wrote: > Just try to read something from Claudius Ptolemy who lived from 85 to 165 a > few centuries before "The year China discovered longitude" > > You can find that he explains how to use eclipses to find the longitude of > places I suspect Kieran Kelly's question is about the practicalities of actually finding your longitude by lunar eclipses, rather than coming up with the concept of doing it. Did Ptolemy find his longitude by this method? I don't know; but it would seem surprising if he had. Kieran Kelly asks whether the list can think of a way the Chinese could have done this in the 15th century. Philip Bailey 50:49N 0:6W
