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Joshua Slocum – Sailing Alone Around the World

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Written by netkingcol

September 16, 2013 at 8:19 pm

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

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

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