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Re: Eclipses of Jupiter's moons: Did ships tend to carry the requisite equipment?
From: William Allen
Date: 2004 Feb 13, 09:48 -0800
From: William Allen
Date: 2004 Feb 13, 09:48 -0800
Carl, In my readings of this epoch of the Royal Navy, it would have been very rare indeed for an average captain (average wealth and skills) to own and carry on board such a telescope and to know how to use it to take these type of sights - and reduce them to useable longitude data. I have not found any precedent for this type of activity in O'Brian's alleged role model for Aubrey (at least for the early books), the famous super-captain Thomas Cochrane. See for example "The Autobiography of a Seaman" by Admiral Lord Cochrane, first published in 1860 with many subsequent re-issues. However, I have read all the Aubrey/Maturin novels and it seems to me that the author (pseudonym O'Brian, an Englishman born Richard Patrick Russ, who in reality did not ever serve on-board a Royal Navy ship during his stint in the armed forces during WWII) is depicting his central character as a science dilettante who is willing to experiment with new astronomy and navigation ideas. I believe Aubrey has even submitted one or more papers to the Royal Society on the "Nutations of the Earth", which I believe had something to do with the procession of the poles. This makes him a worthy colleague for the cerebral and multi-talented doctor (not just surgeon), Steven Maturin. And "Lucky Jack" Aubrey would have had the money from his prize winnings to purchase the needed equipment for Jupiter's moons sights -- at least in the middle of his career before he starts to squander his savings. Certainly there were some Royal Navy ships that carried special equipment with specially trained officers to perform the sights of Jupiter's moons on distant shores (read on the land), but I am under the impression that these trials were earlier (maybe 1760 to 1780? Perhaps under the instigation of Maskelyne or his cronies?) than Aubrey's captain's commission. I have always viewed the Jupiter's moons sights as a slight literary license that -- although historically had been done -- was primarily included to enhance the reader's impression of the intelligence and scientific prowess of the Aubrey character. However, this has not in any way taken away my enjoyment and enthusiasm for the books. Bill Allen -----Original Message----- From: Navigation Mailing List [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM] On Behalf Of CarlZog Sent: Friday, February 13, 2004 8:49 AM To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM Subject: Eclipses of Jupiter's moons: Did ships tend to carry the requisite equipment? A question arose on a mailing list of Patrick O'Brian fans that I thought this group may be better prepared to answer: Apparently, in one of his books, O'Brian's main character is carrying a fairly substantial telescope on board with which to determine longitude by the eclipses of Jupiter's moons. Presumably, he would be conducting these measurements on some remote coastline and not on board. But even assuming that much, the question was, how likely was a British naval ship or its captain to have carried or used such equipment circa 1800? His fan are prone to believing that most of O'Brian's details are drawn from contemporary source material. While the method is commonly discussed in texts of the period, I'm uncertain how prevalent the actual practice was. Carl Herzog -----Original Message----- From: Navigation Mailing List [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM] On Behalf Of CarlZog Sent: Friday, February 13, 2004 8:49 AM To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM Subject: Eclipses of Jupiter's moons: Did ships tend to carry the requisite equipment? A question arose on a mailing list of Patrick O'Brian fans that I thought this group may be better prepared to answer: Apparently, in one of his books, O'Brian's main character is carrying a fairly substantial telescope on board with which to determine longitude by the eclipses of Jupiter's moons. Presumably, he would be conducting these measurements on some remote coastline and not on board. But even assuming that much, the question was, how likely was a British naval ship or its captain to have carried or used such equipment circa 1800? His fan are prone to believing that most of O'Brian's details are drawn from contemporary source material. While the method is commonly discussed in texts of the period, I'm uncertain how prevalent the actual practice was. Carl Herzog
