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Joshua Slocum in Google Earth: Mauritius to Port Natal

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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:


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: Rodriguez to Mauritius

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Slocum sails from Rodriguez on 16Sep1897 and the Spray covers the 330 nautical miles to Mauritius in a little over three days. Again there is disbelief followed by surprise when it is learnt that he is sailing alone. The port doctor considers he must be well to have sailed so far alone and gives him free pratique – the licence that grants access to a port which certifies that the ship is free of contagious diseases.

Once more there is a keen interest in his voyage; he gives a lecture at the opera house [Port Louis Theatre?] and he meets the local dignitaries including the mayor, the governor, and the American consul.

He stays on the island for a little over 5 weeks — from 19Sep to 26Oct:

At Mauritius, where I drew a long breath, the Spray rested her wings, it being the season of fine weather…It was still winter off stormy Cape of Good Hope, but the storms might whistle there. I determined to see it out in milder Mauritius, visiting Rose Hill, Curipepe [Curepipe], and other places on the island.

He visits the governor’s residence at Reduit and, at the flower conservatory near Moka, a botanist names a newly discovered plant Slocum.

A group of seven young ladies persuade Slocum to take them for a sail “tomorrow”. The problem, he soon remembers, is that he has already agreed to dine with the harbour-master, Captain Wilson on the same day. He hatches a plan to take the women to sea but to make the voyage as rough and uncomfortable as possible so they will want to turn back, allowing him to make his dinner appointment.

The plan backfires:

We sailed almost out of sight of Mauritius, and they just stood up and laughed at seas tumbling aboard, while I was at the helm making the worst weather of it I could…The more the Spray tried to make these young ladies sea-sick, the more they clapped their hands and said: “How lovely it is!” and “How beautifully she skims over the sea!” and “How beautiful our island appears from the distance!” and they still cried “Go on!”

He has to sail over 15 miles out to sea before they are ready to return. The yacht soon reaches the island but Slocum makes the mistake of sailing close inshore towards Port Louis:

…for as we came abreast of Tombo [Tombeau] Bay it enchanted my crew. “Oh, let’s anchor here!” they cried.

Slocum doesn’t get the Spray back to Port Louis until the following day for the young ladies insist on going for a swim in the surf and then sleeping on board overnight. They sleep on deck under a tent of sail.

Next day, Captain Wilson himself appears in the launch to tow them all back to Port Louis.

The section of Joshua Slocum’s journey reported here opens 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:

Copyright © Colin Hazlehurst, 2012

Joshua Slocum in Google Earth: Keeling Cocos to Rodriguez Island

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After five weeks at the Keeling Cocos islands Slocum points the Spray in the direction of Rodriguez Island. On this course the wind and the seas are abeam which makes for an uncomfortable voyage; the yawl rolls unpleasantly and Slocum is drenched when he ventures on deck; yet the Spray holds her course faithfully.

A discrepancy appears between Slocum’s assessment of his position by mental calculation and what the log is telling him. He trails a four-bladed rotator which gives him a measure of the Spray‘s speed through the water. After 15 days the log  differs from his own estimated position by 150 miles. Distrusting the instrument, and knowing his ship well, he “kept an eye lifting for land.”

He notices a stationary patch of cloud beyond the horizon while the clouds of the trade-wind float on their way. He says: “this was a sign of something”; that something, of course, being an island with the cloud forming above its mountains. Sure enough, as he sails on, the dark outline of Rodriguez Island appears ahead.

Hauling in the log, he finds that two of its impeller blades are bent out of shape, probably crushed by a shark; this explains the discrepancy and Slocum’s fine judgement is vindicated once again.

He arrives on the windward side of Rodriguez which is not very welcoming; he hauls around to the leeward side of the island where a pilot comes out to the Spray to guide her through the narrow channel between coral reefs that leads to the inner harbour of Port Mathurin, the village that is the capital of the island.

Slocum has looked forward with relish to this land of plenty and a return to relative civilisation:

For many days I had studied the charts and counted the time of my arrival at this spot, as one might his entrance to the Islands of the Blessed, looking upon it as the terminus of the last long run, made irksome by the want of many things which, from this time on, I could keep well supplied.

On the first evening ashore, in the land of napkins and cut glass, I saw before me still the ghosts of hempen towels and of mugs with handles knocked off. Instead of tossing on the sea, however, as I might have been, here was I in a bright hall, surrounded by sparkling wit, and dining with the governor of the island!

Slocum stays on Rodriguez for eight days, replenishing his supplies with, among other items, sweet potatoes and pomegranates. It’s still too soon to head for the Cape of Good Hope, so the next step of the voyage is the short hop to Mauritius…

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

Copyright © Colin Hazlehurst, 2012

Joshua Slocum in Google Earth: Christmas Island to Keeling Cocos

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It’s 550 miles to the Keeling Cocos island group from Christmas Island. The atoll represents a low-lying target less than ten miles across, so Slocum is aware that careful navigation is required. With his old tin clock that has only a working hour hand this will clearly be a challenge.

Using decades of sailing experience, he reads the future in the sky and in the waves. Seeing high cloud that cuts across the trade-wind pattern, he deduces that a storm is brewing in the direction of the Cape of Good Hope and adjusts his course accordingly to allow for the different combination of wind and current that this brings.

Five days later, his intuition is rewarded when he sights the coconut trees of Keeling Cocos ahead while he is half way up the mast. The relief is so great that he slides down the mast, sits on the deck, and “gives way to his emotions.” He has achieved a remarkable feat and part of it belongs to the Spray‘s ability to hold a course :

I didn’t touch the helm, for with the current and heave of the sea the sloop found herself at the end of the run absolutely in the fairway of the channel. You couldn’t have beaten it in the navy!

Slocum stays on the islands for five weeks; remember he’s allowed himself a leisurely pace so he doesn’t arrive too soon off the Cape of Good Hope. Apart from that, why shouldn’t he linger here? After all: “If there is a paradise on this earth it is Keeling.”

The Spray is hauled ashore for some routine maintenance; then his attempt to haul her afloat fails, and the children of the island are delighted to think that a kpeting (a crab) is holding her down by the keel.

Later, Slocum decides it would be a good idea to ditch a few tons of cement ballast and in its place to carry away some of the giant clams called Tridacna. What isn’t such a good idea is to set off across the bay with one of the locals in:

…a rickety bateau that was fitted with a rotten sail, and this blew away in mid-channel in a squall, that sent us drifting helplessly to sea, where we should have been incontinently lost. With the whole ocean before us to leeward, I was dismayed to see, while we drifted, that there was not a paddle or an oar in the boat! There was an anchor, to be sure, but not enough rope to tie a cat, and we were already in deep water. By great good fortune, however, there was a pole. Plying this as a paddle, with the utmost energy, and by the merest accidental flaw in the wind to favour us, the trap of a boat was worked into shoal water, where we could touch bottom and push her ashore.

After this escape, he presses on with his Tridacna plan but uses a safer boat to gather them.

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

Copyright © Colin Hazlehurst, 2012

Joshua Slocum in Google Earth: Thursday Island to Christmas Island

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A few days after the celebrations on Thursday Island to mark Queen Victoria’s diamond jubilee, Slocum sets sail. He heads westward, out into the Arafura Sea, passing Booby Island on the way. He has seen the island before, about 30 years back, but then he was in a fever (possibly contracted in Batavia for his ship, the Soushay, was Sydney-bound from that port), and it was only through an act of will that he dragged himself on deck to see it.

While the sea is relatively shallow he sees many sea snakes writhing and tumbling in the waves and, because the waning Moon leaves the nights dark, he is treated to a fiery display of phosphorescence¹:

It was my good fortune to enter the [Arafura] sea on the last quarter of the moon, the advantage being that in the dark nights I witnessed the phosphorescent light effect at night in its greatest splendour. The sea, where the sloop disturbed it, seemed all ablaze, so that by its light I could see the smallest articles on deck, and her wake was a path of fire.

The weather is serene and the trade winds favourable. Slocum takes this northerly route in order to enjoy these conditions; he has no desire to go around the Cape of Good Hope before the middle of the southern summer and he finds that this plan gives him the time to loiter among the islands along the way.

Even so, as an inveterate sailing ship master he wants to get the best speed out of his vessel. For whatever reason he is dissatisfied with the Spray‘s pace and to remedy this he sets his flying-jib as a spinnaker², using as a pole “the stoutest bamboo that Mrs. Stevenson had given me at Samoa.”

As in the Pacific, the Spray holds her course with remarkable accuracy and for days on end he finds the latitude at noon to be 10° 25’S.

By 02Jul1897 Slocum sees the island of Timor to the north; the next day he passes close by Dana Island off the western end of Timor and smells the fragrances wafted offshore by a breeze. He has crossed the Timor Sea and he enters the Indian Ocean heading for Christmas Island about 1,000 miles distant, arriving eight days later on 11Jul1897.

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


1. Using  TourMaker I simulated the phosphorescence that Slocum saw by stretching out a white strip to keep pace with the Spray.

2. I needed to create another model to show the flying-jib set as a spinnaker. While I was about it I swung out the mainsail boom to give a goose-wing effect.

Copyright © Colin Hazlehurst, 2012

Joshua Slocum in Google Earth: Waterloo Bay, St. Kilda and Launceston

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Joshua Slocum shelters for three days in Waterloo Bay on Wilson’s Promontory in the company of a few whaling boats. Then, in more moderate weather, he sails to Melbourne and picks up a tow at the entrance to Port Phillip Bay. On Christmas Day, 1896, the Spray is anchored in the Yarra River (which he calls the Yarrow), but Slocum soon moves to St. Kilda.

He catches a shark and puts it on display, along with the 26 cubs born by Caesarean section. He charges sixpence per visitor, having set up this enterprise to cover the cost of port charges incurred here. Apart from at Pernambuco (Recife) in Brazil, where he has some history with the regime, these are the only other fees he has to pay on the whole voyage.

News comes in of unusually large amounts of Antarctic ice drifting northwards, bringing with it much stormy weather. Slocum’s plans change again. Rather than head west to battle around Cape Leeuwin he opts to spend time in Tasmania while the season’s change enough to make an easy passage through the Torres Strait; in other words, he intends to sail up the east coast of Australia inside the Great Barrier Reef, where, reaching warmer waters, he would sail round Cape York and into the Indian Ocean.

He sails from St. Kilda on 24Jan1897 and in strong and favourable winds it’s only a two-hour trip across to Tasmania. He reaches the mouth of the Tamar River and follows its meanderings up to Launceston which is about 30 miles inland. The Spray is grounded, on account of arriving at the top of an exceptionally high tide and she eventually has to be dug out:

The Spray was berthed on the beach at a small jetty at Launceston while the tide driven in by the gale that brought her up the river was unusually high; and she lay there hard and fast, with not enough water around her at any time after to wet one’s feet till she was ready to sail; then, to float her, the ground was dug from under her keel.

In this snug place I left her in the charge of three children, while I made journeys among the hills and rested my bones for the coming voyage, on the moss-covered rocks at the gorge hard by, and among the ferns I found wherever I went.

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

To ‘sail’ the 3D model of the Spray up the Tamar to Launceston is not something I would have attempted without the use of the TourMaker tool. The model has to follow the meandering of the river and to be scaled appropriately, and this would have been very laborious to create using hand-written <gx:tour> directives.

Using TourMaker, I was able to create a series of Placemarks, positioned along the course of the river, and generate the tour automatically. Now, of course, I will need to get the Spray down the river again, but using the same Placemarks in reverse order, this should be quite straightforward.

Copyright © Colin Hazlehurst, 2012

You might also enjoy Cook’s first voyage round the world at:

Captain Cook in Google Earth: Batavia to Cape Town

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Endeavour sailed from Batavia on 27Dec1770. It was slow progress at first and they had to anchor the ship frequently to avoid losing ground against contrary tides and currents.

In Sunda Strait, the ship sailed within 3 miles of the island of Krakatoa, which must have had a very different appearance in January, 1771, than it did after its violent eruption in 1883.

Cook stayed over a week anchored off Prince’s Island, at the south-east end of the strait, to stock up on wood, water, and food before making the journey across the Indian Ocean to the Cape of Good Hope. They set sail on Tuesday, 15Jan1771 and progress was still slow owing to light and variable winds.

(See my previous post about the deaths of 23 members of the crew from dysentery)

Once she was in the south-east trade winds, Endeavour started to cover between 100 and 150 miles per day, arriving rather abruptly, and surprisingly, off the African coast on Tuesday, 05Mar1771:

In the evening some people thought they saw the appearance  of land to the Northward; but this appear’d so improbable that I, who was not on deck at this time, was not acquainted with it until dark, when I order’d them to sound, but found no ground with 80 fathoms, upon which we concluded that no land was near. But daylight in the morning proved this to be a mistake by shewing us the land at the distance of 2 Leagues off (about 6 miles).

Cook began to appreciate the strength of the currents that had carried Endeavour to the west and the south of her position determined by dead-reckoning. Remember that Cook did not yet have access to one of John Harrison’s chronometers and the determination of longitude was still a tricky business (though Cook was one of the most meticulous observers). On Wednesday, 13th Cook wrote in his journal:

Latitude observed 34 degrees 15 minutes South; Longitude in, by our reckoning, corrected by the last observation, 341 degrees 7 minutes West, or 18 degrees 53 minutes East from Greenwich, by which the Cape lies in 34 degrees 25 minutes South Latitude, and 19 degrees 1 minute East Longitude from Greenwich, which nearly agrees with the observations made at the Cape Town by Messrs. Mason and Dixon in 1761; a proof that our observations have been well made, and that as such they may always be depended upon to a surprizing degree of accuracy. If we had had no such guide we should have found an error of 10 degrees 13 minutes of Longitude, or perhaps more, to the East, such an effect the current must have had upon the ship.

I assume that the men Cook refers to were the British experts Charles Mason (astronomer) and Jeremiah Dixon (surveyor) who were commissioned in 1763 to resolve the border dispute between the British colonies of: Pennsylvania, Maryland, Delaware, and West Virginia. They had been in Africa because, like Cook, they were despatched on a mission to observe a transit of Venus (the 1761 transit). They never reached their destination of Sumatra and instead were forced to observe the transit from the Cape of Good Hope.

You can now view the part of Cook’s first voyage round the world between Batavia and Cape Town by visiting The website has over 15 hours of animation and audio presenting Cook’s voyage in the Google Earth plugin.

Copyright © Colin Hazlehurst, 2012

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