A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2014 Mar 24, 12:43 -0700
Doug, you wrote:
"Recent posts on The Charles W. Morgan got me to wondering what an average day at sea looked like for ships of that time period."
This is, in fact, the primary focus of one of the classes I teach: "Celestial Navigation: 19th Century Methods". That's being offered in five weeks at Mystic Seaport (details at ReedNavigation.com). The class has evolved a bit in the past four years, but the basic idea is to study the "average day" of navigation at sea from the whaling era and apply it to celestial navigation today. There's nothing wrong with those early methods, except that they did not translate well to very fast ships. And the old methods have a number of advantages: no plotting, high reliability, easy to learn, and minimal almanac data requirements.
"I assume that Whaling ships did not have the same daily routine as a naval vessel of the time period (I could be wrong)."
There are many cultures of navigation in any era. Certainly most naval vessel (in what navies?) would be expected to follow more formal procedures. You really have to look at the logbooks to find out what methods were in use in any period. But in the middle of the 19th century, for example during the first forty years of the Charles W. Morgan's existence from 1841 to 1881, you could expect a reasonably close match in navigational methods between a well-equipped commercial vessel (and let's not forget, there was big money in whaling) and a typical US Navy vessel. That said, on any vessel, regardless of "culture" and type, it always comes down to the choices of the vessel's master. History is built on soft rules and endless exceptions.
You listed "day's work" sights from a 1939 Bowditch. That's much too late for the standards of navigation on the CWM. In particular, star sights as well as "lines of position" were relatively rare in the 19th century and in the "Old Navigation" generally. The earliest reference I have seen to a genuine Sumner line of position dates from the 1860s, and even that was a single experimental trial.
"Does anyone know or have a good reference for what they would have been doing in 1841 when the Morgan was launched?"
A good reference? Well, not really. But if you look at the descriptions of the "Old Navigation" versus the "New Navigation" in early/mid-20th century navigation manuals, you will get a pretty good idea. Commercial "merchant marine" vessels in the Second World War were operating under those same rules, almost identical to the navigation of the Morgan a century earlier. As always, I recommend Mixter's "Primer of Navigation" from c.1943 for this. Of course Mixter is speaking negatively at that point, trying to persuade navigators to abandon those old methods.
Of course, I can just tell you what they were doing. Navigation aboard the Morgan was completely standard 19th century navigation. Dead reckoning was critical. For celestial navigation, they shot the Sun at noon for latitude, time sights in the morning or afternoon or both for longitude (*), and in the early period, they shot very occasional lunars to test the chronometer. The calculations were highly standardized and efficient, even beyond whaling vessels, and it seems that these methods hardly varied from one navigational culture to another from the evidence that I have seen myself. There were undoubtedly exceptional sights on every voyage in that era, and you do find navigators shooting meridian star sights in the middle of the night for latitude once in a while (though not ever on the Morgan as far as I have seen). Late in the 19th century, navigators gradually adopted some Sumner-style line of position techniques, but they were not widely popular until the early 20th century. Amplitudes for compass variation/declination checks were part of the day's work in the early 19th century but by the middle of the century, they seem to have been rare. Presumably the variation was considered a "known" quantity (right or wrong) by mid-century. This, by the way, is one case where the regimen of naval practice may have been superior. It's not difficult to observe an "amplitude" to check the compass, and in fact it's possible that there are few references to the process in mid-19th century logbooks simply because it was a mundane and simple task.
*Time sights were called observations for "finding the true time" back then. If you go digging for the methods in old navigation manuals, that's usually what you have to look for.
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