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Re: Longitude by compass variation
From: Adrian F
Date: 2025 Jun 4, 06:01 -0700
From: Adrian F
Date: 2025 Jun 4, 06:01 -0700
The expedition of around 1700 which I believe led to the chart is described in detail in a book “Halley’s Quest, A Selfless Genius and his Troubled Paramore” by Julie Wakefield. A link to the book is at reference no. 57 in the Wikipedia page on Edmond Halley. The Wikipedia page itself contains a briefer account of the expedition.
As an aside, I saw a paper at archive.org, “A theory of the Variation of the Magnetical Compass” by Mr Ed. Halley, having evidently been published some 20 years before in June 1683, in the Philosophical Transactions of the Royal Society. https://archive.org/details/philtrans08124708/page/n13/mode/2up
Regards,
Adrian F
