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Friday, 3 February 2017

At sea

After a thoroughly enjoyable seven months in Australia and New Zealand, we have now set out on the long road across the far south Pacific to Chile.

The first 0.4% of our voyage was certainly a gentle introduction! Anyone who has traveled the ferry route between New Zealand's South and North Islands will be familiar with the hill-enclosed passage along the quiet waterways of Queen Charlotte Sound and Tory Channel. While a gentle rain did dampen the view, there were no waves or wind to speak of and the only motion was a subtle swirling from the tidal currents in Tory.

Then, as if to remind us that this was to be an OCEAN crossing, our first night out featured winds up to 40 knots (70 kilometers per hour). We kept reducing sail to control forces on the rig until there was very little left at all - and still we kept galloping along. By morning, the front had passed and all was gentle sailing in the sunshine. That will certainly not be the last gale we experience on this crossing!

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A digression for trivia buffs: When we speak of "miles" in these blog postings, we always mean "nautical miles". Until recently, marine navigation (and until the 1970's, long distance air navigation) used a branch of mathematics called spherical trigonometry to calculate position using the sun, planets and stars. The answers came out as angles measured along the earth's surface rather than as distances. It was thus convenient to use an angular measure for distance. The nautical mile was born ... equal to one minute of arc or one sixtieth of a degree measured on the earth's surface. Thus one degree of latitude spans 60 nautical miles. In a comparison to units commonly used on land, one nautical mile is 6080 feet (15% longer than an American/British mile) or just under 2 kilometers.

Speed in ships (and planes) is measured in knots (not nauts and not knots per hour!) equal to one nautical mile per hour. 150 years ago, speed would be measured with the help of a long reel of rope terminated in an edge-weighted floating block of wood that would grip the water. Along the rope at calibrated distances were a series of knots. The block was thrown in the water and, as the rope unreeled into the ship's wake, a sailor noted when the first knot ran through his hand. He turned a sandglass to start timing and counted knots as they ran off the reel. The number of knots in the rope that passed through his hand before the sandglass ran out was the measure of the ship's speed.

Today, with knot reels now many years in the past, container ships make 22 knots through the water while airliners high overhead cross oceans at a speed of 480 knots!

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As I write this, Picton, our point of departure, is 220 miles to our northwest as we make our way at 7 knots towards Valdivia, Chile some 4700 miles ahead. Eastbound sailing voyages across the South Pacific are made in the forties of south latitude to take advantage of the west winds prevailing there. This ocean area has long been known as the "roaring forties" because the winds blow with considerable strength - more than we really need or would like in a small vessel. But it DOES move a boat along.

The routes here were the last bastion of sailing cargo ships as they could still compete economically with the steamship when it arrived on the scene. 3000 ton square-riggers carried grain from Australia to Europe right up until the start of World War II - long after steamships had taken over all trade in the northern hemisphere.

From day to day, our route is re-planned to take advantage of the ever-shifting weather patterns and to avoid any particularly violent storms by shifting to the north or south or by slowing down to allow a weather system to advance ahead of us.

In a couple of days we will pass near the Chatham Islands, a New Zealand outpost marking the 10 percentile of our trip. That will be our last milepost - a quick glance at a map shows no islands at all across the rest of the ocean. Our distance from land will gradually increase to just over 1000 and then will stay at that figure for most of the crossing. Our feeling of progress will come from resetting the clocks an hour every four or five days and from noting which of a succession of inhabited islands or cities lies far far to the north of us.

We have many miles to go!

At 2/3/2017 12:13 (utc) our position was 42°58.32'S 178°21.22'E

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