A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Frank Reed
Date: 2010 Apr 13, 17:02 -0700
George H, you wrote:
"Frank has wasted no time in getting to grips with the log of the Bounty
voyage, and that of the Reaper, and mapping them out for us."
Just to clarify, the Reaper voyage is one that I have discussed a couple of times at presentations at Mystic Seaport. Some NavList members may recognize the outbound portion of the journey from those earlier events.
And you wrote:
"Commendable, and useful, he has created the best map I've seen of the Bounty voyage."
Hey thanks. Glad you liked it. :)
"Thanks for pointing-out of the website at www.fatefulvoyage.com , which was
quite new to me. Does anyone know who put that website together? It seems a
very competent job, but there's no name that I could find. Actually,
Internet Explorer failed on me whenever I tried to get in to that site, but
Firefox managed it successfully."
I had a similar difficulty at another spot on that web site. I also couldn't find the creator's name. Pretty impressive though, huh?
Of the Bounty voyage, you wrote:
"Bligh was on a government-backed enterprise in a Royal Navy ship, to take a
consignment of breadfruit plants from Tahiti to the West Indies, for the
benefit of the British slave-owners as a source of cheap food for their
labourers. He was provided with the best, so it was in no way a typical
voyage at that early period."
Right. I chose it to compare with the Reaper voyage because it's about as good as it gets for a non-scientific mission. Bligh was a highly competent navigator who had first-hand experience of the work of nautical astronomers with Cook, but he was not a nautical astronomer himself. He was an officer with a job to do, and his sextant and his lunars were a means to that end rather an end in themselves. And Bligh was on a mission related to the economics of the colonial system, and thus not a normal "navy" mission, but it was also not a voyage purposefully devoted to exploration, except as suited Bligh's own interests. So it's navigation rather than mapping or surveying work. You had asked last month whether I thought it was possible that British navigators had worked to a higher standard than Americans in the same period. I think anything's possible, but I prefer to see evidence. The evidence from the Bounty logbook shows navigational practice which is very similar, and yet different in fascinating ways, from the evidence in the Reaper logbook. The general pattern of lunars taken around First Quarter and Last Quarter phases of the Moon, when necessary (but certainly not always --sometimes whole months are skipped), and very occasional lunars at other phases is a pattern that I have seen many times before. It's not a law or a "navigation rule" or even "recommended practice" as written down in navigation manuals. It's just the way that things were done, and this "lunars on the quarters" practice lasts right through the 1840s on American whaling ships. This hard, direct evidence from the Bounty's logbook also does confirm my general impression, which I've described before on rather limited evidence, that the American navigators were simply twenty years behind their counterparts in England during this whole period from the late 18th century and on into at least the late 19th century. The sophistication of the navigation aboard the Reaper in 1809 was not significantly different from that aboard the Bounty in 1788. But it WAS two decades later...
"I have one suggestion. That map, being of nautical tracks, could be
improved, in my view, by being put on to a Mercator chart, which preserves
rhumb-line courses without distortion."
While I do appreciate the suggestion, and I agree with your point about rhumb-line courses, the Mercator projection suffers as always from its lack of scale invariance and tends to greatly magnify the apparent significance of any maneuvers in high latitudes like that of the Bounty near Cape Horn and elsewhere. Every flat map projection has major flaws over large enough areas, and I think a possible solution would be to put these things on Google Earth (or any other 3d mapping environment) so that we could roll the globe around to look at the tracks in proper perspective.
For general interest, I'll attach a similar analysis which I prepared a few years ago from the whaleship "Stonington" on a whaling voyage in the 1840s. Like the others, the yellow squares represent individual lunars. This chart doesn't indicate moon phases, but as I recall, this was a typical case and the occasional lunars were taken mostly when the Moon was near First Quarter or Last Quarter. Of course, lunars are almost over at this late date so they are few and far between, but the tradition continued on these vessels.
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