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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 12:51pm PT
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Reilly. They took one chronometer on the Caird, the one in the pictures.
I don’t know of any chronometers which have artificial horizons. It’s pretty certain that if there were an artificial horizon, it would be on a sextant.
From memory, I think they had six of those on the expedition, ( or they took six from Endurance) but it’s been years since I read the books. Several were to be used to reach the pole or cross Antarctica, the purpose of the expedition.
And an artificial horizon is used at sea, especially in polar waters wher often a sun sight is only through a break in the clouds and the horizon is though to sight.
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Reilly
Mountain climber
The Other Monrovia- CA
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Jan 28, 2019 - 12:59pm PT
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Brain fart about chronos with art hor. 🤡
Kinda surprised they only took one sextant on the Caird. Talk about putting all yer eggs in one sextant!
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 01:04pm PT
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It was a polar expedition. At least some of the chronometers would have gone on the sleds. They probably ditched them as superfluous when Endurance sank.
And I’ll bet some were left on Elephant island
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 01:11pm PT
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Brain fart about chronos with art hor. 🤡
Well, some were gymballed for accuracy, so maybe....
[edit] that thing is called a quartz box clock, not a chronometer, by Weems.
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 03:11pm PT
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( shown with the star finder scope reputed to have “fantastic” optics.)
Shackleton geeks have worked which sextant was used to death, it turns out.
Shackleton and Worseley were both Ships masters and would have had their own sextant, as did Endurance’s navigator, Hudson.
Shackleton and Hudson owned Hezzanith sextant of a triangle design. Worseley owned a bell pattern design Hezzanith sextant.
The one Worseley used on the Caird voyage according to him was the one he borrowed from Hudson. There is no horizon bubble on it
In his book he describes taking sights from wave top while being lashed to the mast and held by shipmates.
Several sextants get paraded around as being Shackleton’s sextant used on the James Caird. Apparently that is less than accurate.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 28, 2019 - 03:26pm PT
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Thanks, Lorenzo! Who knew? Navigation and Shackleton geeks aside, that is.
Most of Worsley's observations would have been taken on and near Endurance, while she was frozen in the ice. In other words, from a remarkably stable platform. The observations from the voyages to Elephant Island, and then South Georgia, being in quite another class.
We must Endeavour (Cook's ship, the command module on one of the Apollo missions, and one of the space shuttles), so as to have Endurance. Fortitudine Vincimus
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 03:54pm PT
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I’ll admit to being a little bit of a Shackleton geek myself. It’s hard not to be fascinated by the whole endeavor. ( endeavour?.. no wait. That was Cook)
When I was a kid I shipped aboard a pleasure cruise between Long Island and Bermuda. I took sights on pretty calm Gulf Stream waters. One day in the middle of the voyage the guy who owned the boat took my sights without checking them, which focused my mind.
I’m not sure what it would have been like in the conditions Worseley had.
Now you can just use the GPS on your iPhone.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 28, 2019 - 04:35pm PT
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^^^Perce Blackborrow, the stowaway. Crean looked a LOT tougher.
Wooden vessels usually had a cat to keep down rodents, who was frequently named "Mrs. Chippy". The ship's carpenter of course being Mr. Chippy. Somewhat ahead of its time, Mrs. Chippy on Endurance was male.
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 04:36pm PT
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You might be right. I’m working from memory.
Blackborow. Signed on as first to be eaten.
He foiled that Plan by getting gangrene. Spoiled meat.
I’m sure that is mrs Chippy.
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 04:53pm PT
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Tom Crean with pups ( also murdered)
Crean was a shipmate from the Discovery Expedition, 1901–04, and had also been with Scott's Terra Nova Expedition in 1910–13, where he had distinguished himself on the fatal polar march.
He was the second guy Shackleton chose after Worseley for the Georgia island trip.
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 05:27pm PT
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Hey! I got an idea.
Let’s go sail 800 miles in the Southern Ocean.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 28, 2019 - 09:38pm PT
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There's also the Sextant Handbook: https://www.celestaire.com/product/the-sextant-handbook/
My father, a professional engineer with considerable experience surveying, thought it was quite good.
From Amundsen's "The South Pole": Among the instruments belong to the Fram I may mention a pendulum apparatus, an excellent astronomical theodolite, and a sextant. Lieutenant Prestrud studied the use of the pendulum apparatus under Professor Schiotz and the use of the astronomical theodolite under Professor Geelmuyden. We had in addition several sextants and artificial horizons, both glass and mercury." Also "Of the instrument and apparatus for the sledge journeys we carried two sextants, three artificial horizons, of which two were glass horizons with dark glasses, and one a mercury horizon.." They used the artificial horizon at the pole.
Shackleton's "South" simply refers to their taking a 'sextant' on James Caird. No details, although probably their log says more.
So state of the art, using artificial horizons, given that Fram sailed from Norway in midsummer 1910. Most such equipment then was made in Germany, and I suspect that the manufacturers got good promotion out of sending it to polar regions.
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Lorenzo
Trad climber
Portland Oregon
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Jan 28, 2019 - 09:51pm PT
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Most such equipment then was made in Germany, and I suspect that the manufacturers got good promotion out of sending it to polar regions.
The threee sextants mentioned were ‘Hezzanith’ models made by Heath & co, New Eltham, London.
After a couple buyouts, they are still made, though modern ones are aluminum alloy.
I doubt the Admiralty would have been in the habit of purchasing instruments from a foreign power.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 29, 2019 - 01:59pm PT
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Good point. It'd be interesting to learn the origins of the scientific and navigation instruments taken on the various expeditions, not just sextants. By 1910 German scientists and engineers, and European scientists and engineers generally, had in many ways surpassed the British, so the quality of their instruments may have been a bit better.
For the 1903 - 06 voyage of Gjøa through the Northwest Passage, Amundsen got instruction in measuring magnetic fields, and instruments, in Germany, which was then leader in that field. Likewise it's interesting that in 1909 - 10 he went to Germany for much of his instrumentation - when he could have had his pick.
Of course, all the polar expeditions of that time were heavily staffed with experienced navigators, whatever instruments they had. Shackleton may have been a bit lax - did they really get to within 100 miles of the pole in 1909, based on dead reckoning? - but he's generally accorded that. Amundsen and Scott were scrupulously careful with regard to observations, having learned the Cook/Peary lesson. Although amusingly Amundsen forgot to take the tables for 1912 with him, which meant they had to get to the pole by December 31st.
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Lorenzo
Trad climber
Portland Oregon
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Jan 29, 2019 - 03:03pm PT
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You are making too much of this superior engineering thing. The best chronometers were British ofr Swiss from the Harrison invention on. ( modern quartz watches are probably as accurate)
Sextants, while they are precision instruments, ain’t rocket science.
I made a sextant 60 years ago for a science project that was accurate to about 10’ of arc. Plastic sheet, a couple compact mirrors, a little dime store scope, and a sharpie. I scratched out the degree markings and used a vernier swing arm. To make things easier, I made it about 50% larger than a normal sextant.
Since one minute of arc equals one nautical mile of latitude, that’s the ten miles Worseley was claiming as his accuracy with his sights. At 60° south latitude, longitude sightings would be twice that accurate since one minute of arc longitude is a half mile at 60°
The moon or sun look pretty big in the sky. Their diameter is only 30 minutes of arc.
There is a Davis mark 15 sextant that is accurate to about 3-5 miles that is made of molded ABS plastic like a Revelle model airplane.
https://www.starpath.com/catalog/accessories/1840d15.htm
That’s line of sight to your objective.
An even cheaper Mark 3 has been around for more than 50 years and is in lots of emergency kits. I’ve seen them for about $35 and they will get your ten miles.
Even with the best metal sextant, you aren’t getting closer that 1/2 to 1 mile even on dry land. Atmospheric refraction just doesn’t allow any better without LOTs of number crunching that just isn’t done in navigation.s
( refraction of the atmosphere is a lot more near the horizon, and air temperature matters)
Real navigators get better accuracy with multiple sights on different celestial objects. And seeing how lines of position converge.
It just isn’t that big a deal. What’s more important is the user, just as honnold can climb better in bedroom slippers than most of us can in the best sticky rubber
I won’t even get into Sven Yvrind’s bris sextant. Costs maybe a dollar. With care, you can navigate to Worseley accuracy - maybe easier than with a real sextant because you use your head to hold it steady.
https://web.archive.org/web/20071011212818/http://www.cassens-plath.de/catalog_web/096e_web.html
You do have to calibrate it. A day on the beach and some maths.
Then there is the guy who went around the world with no instruments ( not even a compass) and made landfall within 20 miles using only ancient traditional methods and a good star almanac.
http://blog.geogarage.com/2012/09/circumnavigate-globe-without-instruments.html
I think a Polynesian canoe also did it.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 31, 2019 - 09:50pm PT
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Tonight's field trip was to Vancouver's maritime museum, where there was a talk on the discovery of the wrecks of Erebus (2014) and Terror (2016), off the coast of King William Island. It was by Captain Bill Noon, commander of HMCS Sir Wilfrid Laurier - the base vessel. It was very kewl. Neat stuff:
 What's left of the deck of Erebus is about 10 m below the surface, so they can dive there in the spring. They set up on the ice, which is 2+ m thick, hang some big lights underneath, and go to work. Her stern is in the process of caving in, and with increasing exposure to current due to lessening ice in the area, the priority is to protect her. The superstructure and deck seem to have been scoured by large icebergs.
Terror is in Terror Bay. Which was named before her wreck was discovered. Inuit tradition was that it was there, also there was a lot of anecdotal evidence. They searched there because an Inuit from Gjøa Havn said he'd seen a mast protruding in the area, and struck gold after only 2.5 hours with a side scan radar. Except that her deck is almost 30 m below the surface - her masts could never have protruded, as they weren't that high. At any rate, that wreck is in much better condition, and safer from changing conditions, so they're leaving it for now. The bowsprit is even still there! However, they've done some work, which amongst other things shows plates on the tables in the officers' mess. Which in turn suggests that things like the ship's log might still be there, and retrievable, which would provide information as to what happened until she was finally abandoned.
One artifact on Terror was a sextant. It was hard to tell whether it was made in Britain or Germany, but the word "Lorenzo" could almost be made out in tiny letters.
Even though multi-year (tough) ice isn't as common or thick as it once was, the southern Northwest Passage through that area wasn't passable at all in 2018, unless you had a serious icebreaker.
Only about 13% of Canada's Arctic - Hudson's Bay, and everything above 60 north - has been charted to modern standards. The southern passage involves a lot of shallow water, and the northern has more ice.
The exact locations aren't public, are legally protected, and they're watching from satellite. In fact, one of Noon's friends was navigating a private boat through the area, and those who must be obeyed called from a bunker in Ottawa, to ask who it was and what it was doing. No grave robbing allowed.
Captain Noon had some fun stories. When they first found Erebus, they scrambled around to find the "WHAT TO DO IF YOU FIND SOMETHING INTERESTING" manual, which no one had bothered to look at. (Our then prime minister was quite keen on this stuff.) The sort of thing that the multitudes of bureaucracies involved produce. When they found it, the first substantive thing it said was "TOP SECRET". Which, when you're a captain of a coast guard vessel in the Arctic, isn't hard to do. You just have to pull one plug, and there's complete radio silence. No wifi up there. #2, it said that all the senior people had to fly to Ottawa, so the politicians could pose with them. (Obviously written by a bureaucrat who knew little about maritime matters.) So Noon calls the prime minister's office, reports what has happened, and they tell him to fly to Ottawa. Whereupon he in effect says "I'm the captain, and I'll be damned if I'll leave my ship." So the PMO called the officer in charge of the coast guard, who replied. They said "We're calling about Captain Noon", and the officer said "Now what's he done?" In the end Noon stayed with his ship.
(Sir Wilfrid Laurier was one of Canada's great prime ministers, and our first of Quebecois heritage. I went to a school named for him.)
ps Slocum didn't have a sextant!
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Reilly
Mountain climber
The Other Monrovia- CA
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Jan 31, 2019 - 10:12pm PT
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Very good reportage, Mighty, especially about the sextant. What a find!
her masts could never have protruded, as they weren't that high I beg to differ after looking at the various paintings extant of HMS Terror, a proper ship’s name if there ever was. She was 102’ so her main mast would normally have been close to her length as indeed it appears in the paintings. The paintings of her in New Zealand appear to show her with topgallant masts swayed to height of seemingly 130’. In the Arctic she most certainly would not have used her topgallants often. I would think that the Inuit’s story more than credible especially considering the hull has sunk, or collapsed, a good 20’ from its initial position.
Apparently Ottawa bureaucrats have a very poor understanding of their country’s geography, let alone their Coast Guard’s standing orders.
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Mighty Hiker
climber
Outside the Asylum
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Topic Author's Reply - Jan 31, 2019 - 10:21pm PT
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Granted that a mast might have just protruded from the water when Terror first sank - but after 170 years of pounding by ice bergs? Not a chance.
There are scheduled flights to and from Gjøa Haven. Noon could simply have gotten on Laurier's helicopter and flown there, thence to Ottawa. Somehow the PMO would have figured it all out - a few days later the prime minister flew there for the photo op. The expedition had major government backing.
The main feature at the maritime museum is of course St. Roch - second vessel to transit a northwest passage, first to do so from W - E, first to do it both ways, first to circumnavigate North America. As fascinating as Fram in Norway. St. Roch is almost exactly the same length as Erebus and Terror. Granted that she had good diesel engines, but she also had sails, and her crew was usually ten or less. Erebus and Terror had 60 or more, in much the same space.
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Reilly
Mountain climber
The Other Monrovia- CA
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Jan 31, 2019 - 10:22pm PT
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Oh, I was thinking the reference was from BITD. Unnskyld! 🤡
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