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Joshua Slocum in Google Earth: Port Natal to Cape Town

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Follow Joshua Slocum’s Sailing Alone Around the World at: http://www.hazelhurst.net/Slocum

Slocum sails from Port Natal [Durban] on 14Dec1897. The passage to Cape Town is about 800 miles. When the Spray is at her best it would take Slocum about one week to cover this distance; however, he expects the weather to be rough even though he has waited and waited for the southern summer to develop. His expectations are met:

On Christmas, 1897, I came to the pitch of the cape. On this day the Spray was trying to stand on her head, and she gave me every reason to believe that she would accomplish the feat before night. she began very early in the morning to pitch and toss about in a most unusual manner¹, and I have to record that, while I was at the end of the bowsprit reefing the jib, she ducked me under water three times for a Christmas box.

A large English steamer passing ran up the signal, “Wishing you a Merry Christmas.” I think the captain was a humorist; his own ship was throwing her propeller out of water.

Two days later the Spray is passing Cape Agulhas, the southernmost point of the African continent, 13 days from Port Natal and with 120 miles still to cover. The winds are more moderate now, but there is still one more gale to come. He shelters in Simons Bay [False Bay] until the wind slackens then he beats the Spray around the Cape of Good Hope, accurately named by early Portuguese navigators as the “Cape of Storms.”

Thirty-five nautical miles later, the Spray runs into calm water in the shelter of Table Mountain. Slocum is in reflective mood; despite sailing alone for so long he anchors in the bay, “clear of the bustle of commerce”, and takes a day to contemplate his achievement of negotiating both Cape Horn and the Cape of Good Hope single-handed.

The next day, he sails the Spray into dry dock where she remains for three months. Slocum does not record the date of his arrival at Cape Town; perhaps it was two or three days after passing Cape Agulhas, which would make it 29Dec or 30Dec1897.


The section of Joshua Slocum’s journey reported here opens Chapter XVIII of Sailing Alone Around the World, and this post is a trailer for the adventure that I am retelling in Google Earth at:  http://www.hazelhurst.net/Slocum

Notes

1. To simulate pitching and tossing “in a most unusual manner”, I combined animations on all three axes by specifying AnimatedPitch, AnimatedRoll, and AnimatedYaw in the TourMaker Input File for this section of the passage.

Copyright © Colin Hazlehurst, 2012

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Joshua Slocum in Google Earth: Mauritius to Port Natal

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Follow Joshua Slocum’s Sailing Alone Around the World at: http://www.hazelhurst.net/Slocum

Fully provisioned and rested, Slocum sails from Port Louis, Mauritius on 26Oct1897. At first the winds are light and he draws away from the island slowly. By the next day he is passing the island of Réunion. The sea is too rough to consider landing, but a pilot comes out of Galets on the north-west corner of the island when Slocum hands over a Mauritius paper.

A course is set to Cape St. Mary, the southernmost point of the island of Madagascar. The trade winds are weakening now and by 30Oct1897 Slocum finds himself becalmed:

The sloop was now drawing near the limits of the trade-wind, and the strong breeze that had carried her with free sheets the many thousands of miles from Sandy Cape, Australia, fell lighter each day until October 30, when it was altogether calm, and a motionless sea held her in a hushed world. I furled the sails at evening, sat down on deck, and enjoyed the vast stillness of the night.

On the following day, a light breeze carries the Spray past Cape St. Mary. About one week later and for the rest of the voyage to Port Natal (Durban) strong gales batter the yacht and heavy thunderstorms were prevalent¹.

Here the Spray suffered as much as she did anywhere, except off Cape Horn. The thunder and lightning preceding this gale were very heavy.

It takes the Spray 18 days to cover the 800 miles between Madagascar and Durban, an average of 45 miles per day made good. This is less than half the distance per day that she is capable of. In reality, the course is not a straight line because the “succession of gales of wind…drove her about in many directions.” So, the Spray is sailing as fast as ever, but on some crazy zig-zag course dictated by the winds².

Slocum stays in Port Natal for four weeks; he meets all the members of both yacht clubs and sails on the crack yacht Florence; he meets Henry Morton Stanley, the Welsh-born naturalised American who is a renowned explorer of Africa; and he encounters a trio of men who believe that the world is flat. They visit Slocum actually expecting to find information that will support their hypothesis. He must disappoint them:

With the advice [to them] to call up some ghost of the dark ages for research, I went ashore, and left these three wise men poring over the Spray‘s track on a chart of the world, which, however, proved nothing to them, for it was on Mercator’s projection, and behold, it was “flat”.

The Spray sails from Port Natal on 14Dec1897 and is once more: “off on her alone,” as they say in Australia.


The section of Joshua Slocum’s journey reported here concludes Chapter XVII of Sailing Alone Around the World, and this post is a trailer for the adventure that I am retelling in Google Earth at:  http://www.hazelhurst.net/Slocum

Notes

1. Thunder and lightning or rather lightning followed by thunder was a fresh challenge to my animation skills. Again, I used models created in Google SketchUp to represent the effect of lightning; I added to this a couple of thunder tracks from the WavePad sound effect library. Normally I would try to enhance TourMaker by adding a directive that would generate the thunder and lightning automatically. This time I hand-coded it. Each lightning model flashes on and off twice (by setting visibility=1 then visibility=0 ) with each period of visibility lasting about 100ms. A few seconds later the thunder-clap audio is output.

2. I realised that a better animation of a rolling yacht would result from oscillating the angle of roll about the current ‘Roll’ setting, rather than about the vertical. This would create the effect of the yacht being heeled over in the wind while  waves introduce an additional periodic rolling motion. I have amended TourMaker accordingly

Copyright © Colin Hazlehurst, 2012

Joshua Slocum in Google Earth: Magellan Strait to Juan Fernandez Islands

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Follow Joshua Slocum’s Sailing Alone Around the World at: http://www.hazelhurst.net/Slocum.

Slocum breaks free of the Magellan Strait on 13Apr1896 after two months battling against storms and savages. He heads north-west and then more northerly in the direction of the Juan Fernandez Islands, the largest of which was home to castaway Alexander Selkirk for four years (1704-1708). It was Selkirk who inspired Daniel Defoe to write Robinson Crusoe and the island is also known as Robinson Crusoe Island.

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As the days pass, the winds and seas moderate, different birds fly around the Spray, and different fish are in the sea. The latter includes sharks which Slocum, after the reticence exhibited in the lonely Strait of Magellan, feels no compunction about killing. He writes:

On the tenth day from Cape Pillar a shark came along, the first of its kind on this part of the voyage to get into trouble. I harpooned him and took out his ugly jaws. I had not till then felt inclined to take the life of any animal, but when John Shark hove in sight my sympathy flew to the winds. It is a fact that in Magellan I let pass many ducks that would have made a good stew, for I had no mind in the lonesome strait to take the life of any living thing.

Slocum’s navigation is accurate and, combined with the Spray‘s legendary ability to hold a compass course and sail in a straight line, it is not surprising that Robinson Crusoe Island is sighted “right ahead” on 26Apr1896. Nevertheless, Slocum feels quite emotional about this achievement and bows his head to the deck as: “I could find no other way of expressing myself.” Perhaps he is looking forward to human contact again or maybe it’s simply the thrill of reaching another milestone in the voyage.

The Spray arrives off the island as night is approaching. Slocum spends the night in calm winds listening to the waves breaking on the shore and to the cries of the animals in the hills. At daylight a rowing boat comes out to meet him and the crew, after feasting on coffee and tallow-fried doughnuts, tow him into the harbour by the settlement.


This section of Joshua Slocum’s journey concludes Chapter X of Sailing Alone Around the World, and this post is a trailer for the adventure that I am retelling in Google Earth at:  http://www.hazelhurst.net/Slocum

My text of Slocum’s voyage is an unabridged reproduction of the original edition. It contains an error either of printing or of arithmetic. He writes of the approach to Juan Fernandez: “From Cape Pillar I steered for Juan Fernandez, and on the 26th of April, fifteen days out, made that historic island right ahead.”

Oops! 26 minus 13 is 13 days out from Port Angosto and Cape Pillar, not 15. Wikipedant? moi?!

Copyright © Colin Hazlehurst, 2012

You might also enjoy Cook’s first voyage round the world at: http://www.hazelhurst.net/Cook

Joshua Slocum in Google Earth: Port Angosto to the Pacific Ocean

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Follow Joshua Slocum’s Sailing Alone Around the World at: http://www.hazelhurst.net/Slocum.

Laden with tallow and other salvaged cargo, and with her sails white in the snow, Slocum manages, just, to get the Spray into a snug nook in Port Angosto, still 60 miles short of Cape Pillar and the Pacific.

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Slocum now takes the time to refit the Spray. He reorganises the cargo and the cabin; he fixes the sails and rigging; and he adds a jigger mast to convert his sloop into a yawl – all work that is preparing her for the Pacific voyage ahead.

There is another, final, encounter with Fuegians. They sneak up on the Spray while Slocum is at work on the decks and shoot two arrows at him. The first whizzes past into the sea but the second embeds itself in the mast. Slocum raises his trusty Martini-Henry rifle and fires into the bushes. At the first shot, three Fuegians leap up and start running. He keeps firing to make sure they get the message and that’s the last he sees of ‘savages’, though he continues to lay carpet tacks on the deck at night.

After six failed attempts to get out of his anchorage, he sails from Port Angosto on 13Apr1896, but doesn’t escape without first drifting three times round an island, which he names Alan Erric Island after an acquaintance. In the strait, the wind is fair, a strong southeaster, and on the same day he breaks free of the Straits of Magellan, Cape Horn, and Tierra del Fuego, destination – Juan Fernandez, or Robinson Crusoe’s Island.


This section of Joshua Slocum’s journey is the opening section of Chapter X of Sailing Alone Around the World, and this post is a trailer for the adventure that I am retelling in Google Earth at:  http://www.hazelhurst.net/Slocum

Slocum added a jigger mast to the Spray while in Port Angosto, converting her to a yawl (“though I called the boat a sloop just the same”). In 3D modelling terms, this was my first opportunity to use the full, yawl-rigged model and the one that will be used for the rest of the voyage. You might have noticed that for a few days I had the rig changing at Rio de Janeiro but, realising that Slocum only added the semi-circular stanchion there, I created another model that included the stanchion and used that from Rio to Port Angosto.

Note that I couldn’t find Alan Erric Island on a chart so I chose a likely looking one in the harbour and one that it was feasible for me to animate the model around. If you know the exact location of Alan Erric Island I’d be happy to change the Spray‘s track to circumnavigate it, otherwise artistic licence prevails.

Copyright © Colin Hazlehurst, 2012

You might also enjoy Cook’s first voyage round the world at: http://www.hazelhurst.net/Cook

Captain Cook’s First Voyage Round The World

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The following slideshow and image gallery show screenshots taken from Captain Cook’s First Voyage Round The World, a presentation of Cook’s journal containing more than 15 hours of animation and audio.

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To view the presentation, point your web browser to http://www.hazelhurst.net/Cook/ and install the Google Earth plug-in if you don’t already have it installed.

Copyright © Colin Hazlehurst, 2012

You might also like:

If you enjoyed Cook’s voyage, you might also like Joshua Slocum’s Sailing Alone Around the World, a similar virtual re-enactment of a famous sea voyage by the first single-handed circumnavigator; this presentation is still under construction.

 

Captain Cook in Google Earth: Fevers and Fluxes

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His Majesty’s Bark Endeavour arrived in Batavia, Java, on 10th October, 1771. At this point in the voyage, more than 3 years after setting sail from Plymouth, the ship was in a very poor state and in need of a major refit. John Satterly, the ship’s carpenter provided Lieutenant Cook with a description of her defects, the majority of the damage being inflicted when Endeavour ran aground on a reef off Australia:

The ship very leaky (as she makes from 12 to 6 inches water per hour) occasioned by her main Kiel being wounded in many places and the Scarfe of her Stem being very open. The false Kiel gone beyond the Midships from Forward and perhaps further, as I had no opportunity of seeing for the water when hauled ashore for repair. Wounded on her Starboard side under the Main Chains, where I imagine is the greatest leaks (but could not come at it for the water).

By contrast, the men in were in good condition. The diet of his crew was constantly on Cook’s mind and he made every effort to procure fresh produce whenever possible. His journal entry for 15Oct1771 reads:

Monday, 15th. Fresh Sea and land breezes and fair weather. I had forgot to mention that upon our arrival here I had not one man upon the sick list; Lieut. Hicks, Mr. Green, and Tupia were the only people that had any complaints occasioned by a long continuance at Sea.

This was a great success considering the hardships, both physical and psychological, the men had endured. However, a mere 3 weeks after returning to ‘civilisation’ from the privations that attended their voyage of discovery the picture was very different. On Wednesday, 07Oct1771 Cook wrote:

Wednesday, 7th. Employ’d getting ready to heave down in the P.M. We had the misfortune to lose Mr. Monkhouse, the Surgeon, who died at Batavia of a Fever after a short illness, of which disease, and others, several of our people are daily taken ill, which will make his loss be the more severely felt; he was succeeded by Mr. Perry, his mate, who is equally as well skilled in his profession.

And another 3 weeks after this:

Wednesday, 26th. The number of Sick on board at this time amounts to 40 or upwards, and the rest of the Ship’s Company are in a weakly condition, having been every one sick except the Sailmaker, and old Man about 70 or 80 years of age. But notwithstanding this general sickness, we lost but 7 men in the whole: the Surgeon, 3 Seamen, Mr. Green’s servant, and Tupia and his servant, both of which fell a sacrifice to this unwholesome climate before they had reached the object of their wishes.

You have to feel for these men; they had rounded Cape Horn against wind and tide; they had taken their ship across the Pacific to Tahiti to observe the transit of Venus, then turned south to face more violent storms in search of a suspected southern continent; they had circumnavigated both North Island and South Island of New Zealand again with heavy swells and storm force winds; they sailed the whole of the east coast of Australia, sounding with a lead most of the way; they survived the grounding of the ship on the Great Barrier Reef when only their efforts at pump and windlass saved them; they proved there was a passage between Australia and New Guinea; and with a ship that was battered and worm-eaten they had limped to Batavia.

These giants of adventure were laid low by the microscopic organisms of dysentery: viruses, bacteria, protozoans, and parasites of various types. Too little was known of the mechanisms of dysentery and the preventive measures against it and they paid the price. The illness had no respect for rank; Mr. Monkhouse, the ship’s surgeon, Charles Green, the astronomer from the Royal Society, and Sydney Parkinson, natural history painter in the retinue of Joseph Banks, all eventually succumbed to the ‘flux’; and the disease ran through all other ranks including: the boatswain, the carpenter, the sailmaker, and a whole swathe of marines and seamen.

Cook completed his description of Batavia with the following text:

Batavia is certainly a place that Europeans need not covet to go to; but if necessity obliges them, they will do well to make their stay as short as possible, otherwise they will soon feel the effects of the unwholesome air of Batavia, which I firmly believe is the Death of more Europeans than any other place upon the Globe of the same extent. Such, at least, is my opinion of it, which is founded on facts. We came in here with as healthy a Ship’s Company as need go to Sea, and after a stay of not quite 3 months left it in condition of a Hospital Ship, besides the loss of 7 men; and yet all the Dutch Captains I had an opportunity to converse with said that we had been very lucky, and wondered that we had not lost half our people in that time.

What happened next is portrayed in a Google Earth presentation which plots Endeavour’s track after leaving Batavia. She was bound for England by way of the Cape of Good Hope. Not long after passing through the Straits of Sunda and while heading out into the Indian Ocean towards the trade winds, the men began to die. In the next 34 days there were 23 deaths. How very disheartening that must have been for the man who had kept scurvy at bay for 3 years and more.

Clearly, a bracing sea cruise is not the cure for dysentery. Cook felt that matters improved once they reached the trade winds, but the two screenshots above show the trail of death right across the Indian Ocean until Endeavour was to the south of Madagascar. Cook recorded the last deaths as follows:

Wednesday, 27th (February, 1771). Ditto Gales and Cloudy. In the A.M. died of the Flux Henry Jeffs, Emanuel Parreyra, and Peter Morgan, Seamen, the last came sick on board at Batavia, of which he never recover’d, and the other 2 had long been past all hopes of recovery, so that the death of these 3 men in one day did not in the least alarm us. On the contrary, we are in hopes that they will be the last that will fall a sacrifice to this fatal disorder, for such as are now ill of it are in a fair way of recovering.

To view the presentation described above, go to http://www.hazelhurst.net/Cook/ and select ‘Batavia to Cape of Good Hope’ in the menu system; then click on ‘Fevers and Fluxes’.

Copyright © Colin Hazlehurst, 2012

Captain Cook in Google Earth: migration to the web complete(ish)

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I have been working for a couple of weeks converting my Google Earth presentation of James Cook’s first voyage round the world so that it runs in a web browser using the Google Earth API.

All of the Google Earth ‘tours’ are now transferred to www.hazelhurst.net/Cook/ providing more than 15 hours of animation and audio. I hope that education and GIS professionals as well as those interested in adventure, exploration, and discovery, will find this presentation interesting and useful.

There are several advantages to the new site:

  1. The menu system makes it easy to find the part of the voyage that interests you.
  2. All of the legs of the voyage are accessible from the menu; previously you had to load each tour separately into the Google Earth application. The ‘ish’ in the title is there because I have not yet prepared the section of the voyage from Batavia to England and I have not included the passage from Cape Horn to Lagoon Island. For the sake of completeness I will add these sections at a later date.
  3. The tours in the presentation are each limited to about 10 minutes duration, and they now load much faster than they did in Google Earth.
  4. After completing a large part of this project I realised I needed some  automation tools. Consequently, I developed TourMaker which uses <ExtendedData> attached to <Placemark> elements to describe how the 3D model should be moved. This eliminates much of the manual effort required to create animations in Google Earth; this in turn made it easier to model Cook’s voyage in finer detail. I particularly like how Endeavour now rounds Cape Horn and later visits a string of South Seas islands both on the approach to Tahiti and on leaving that island after observing the transit of Venus.
  5. I have made fresh sound recordings of much of Cook’s journal; I bought a copy of WavePad to do this and, as in many other situations, I discovered the need to do the job twice: the first time to learn how to do it, and the second time to do it properly. The early recordings were rushed, the levels were inconsistent, and the sound effects were too prominent. I hope these issues are now resolved.

Copyright © Colin Hazlehurst, 2012

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