thinking outside the tank

Captain Cook in Google Earth: Endeavour Reef

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It may be true that every ship has, somewhere, a reef with her name on it. If so, then H.M.Bark Endeavour found hers at 11p.m. on 11Jun1770. The way it happened was as follows.

In the afternoon, Endeavour was sailing about 10 miles from the coast in a north-westerly direction in 12 fathoms of water. They saw two low islands ahead and, rather than sailing towards them as it grew darker, Cook headed offshore to the north-east into deeper water, or so he thought. He also wanted to know whether there were any islands further out, as documented by an earlier navigator.

At first the plan worked, the water deepening to 21 fathoms. Suddenly, at about 9 o’clock, their soundings were 12, 10, and 8 fathoms; they were heading into shoal water. Cook was about to give the order to let go an anchor, to pull them up short, when the next sounding showed deeper water. He thought they were past the danger and gave the order to ‘stand on’. What had happened was that Endeavour had narrowly missed going aground on a reef which now has the name Pickersgill Reef.

Pickersgill Reef

Endeavour passing over the tip of Pickersgill Reef at 2100 on 11Jun1770

They continued in depths of 21 fathoms for the next two hours then, a few minutes before 11 o’clock, the depth was measured as 17 fathoms. Before the man at the lead could cast the line, Endeavour struck the reef that now bears her name.

Sounding round the ship they found the deepest water astern and tried to heave her off using the anchors. This technique involves dropping the anchor some way from the ship and using a capstan to haul on the chain. A free-floating ship can easily be moved in this way, but Endeavour was stuck fast and heeling to starboard.

They tried to lighten the ship by throwing overboard her guns, ballast, casks, jars, anything in fact that they thought would help. They hauled on their anchor chains again at the next high tide but failed to free the ship, owing partly to a peculiarity of the tides in this region, in which only every other tide reaches a greater depth.

Endeavour Reef

Endeavour ran aground on Endeavour Reef about 2300 on 11Jun1770

Before the next high tide, Cook deployed his anchors in new locations and was ready at 5p.m. when the next flood started to rise. At 9 o’clock, the ship was righted but immediately began to take on water at a greater rate, more than the three working pumps could handle. The situation was becoming desperate. Cook made the decision “to risk all and heave her off.”

Dividing the men between working the pumps and heaving on the anchors, Cook had Endeavour pulled clear of the reef at 2220 on 12Jun1770. She was dragged into deeper water but soon after they felt in worse peril than ever when it seemed that the water level in the hold of the ship, which was 3 feet 9 inches when they got clear of the reef, had risen rapidly by 17 inches.

Rising water level

A mistake soon after happened, which for the first time caused fear to approach upon every man in the ship

What had happened was that the man who had the job of measuring the depth of water in the hold used the ceiling as his benchmark. When he was relieved, the next man measured the depth from the outside plank, and this created the apparent rush of water into the ship. The men “redoubled their vigour” and by 0800 the next morning, the leak was under control, but not yet repaired.

To stem the leak, the ship was fothered. This process involves the preparation of a sail by coating it with oakum, a tarred fibre, and with wool, completed with a layer of “sheep dung or other filth; horse dung for this purpose is the best” (like me, I guess you don’t want to know the source of the ‘other filth’).

The treated sail is hauled under the ship using ropes and positioned, by trial and error, over the hole in the hull. This worked well for Endeavour, and before long the leak could be managed by “one pump with ease”. The men’s spirits soared, and instead of wanting only to limp to the Hope Islands – the small low islands Cook had wanted to avoid in the first place – they thought of ranging alongshore to find a decent harbour where the ship could be beached and repairs made.

Today, I added this leg of Cook’s exploration of the Australian coast to my Google Earth tour which presents his first voyage round the world. If you haven’t looked at the latest Google Earth yet, I can highly recommend it.

Copyright © Colin Hazlehurst, 2012

If you would like to follow Cook’s voyage, you will need to install the latest version of Google Earth on your computer; then go to the Captain Cook blog  and click on the links on the right-hand side of the page, under the ‘Google Earth’ heading. After the animation is loaded in Google Earth, you need to expand an entry in the Table of Contents. You will see a ‘Play’ icon which you double-click to start the animation. Don’t forget to enable your speakers to hear the spoken journal.


One Response

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  1. I am a descendant from lieutenant Richard pickersgill, the reef was named after him, also pickersgill harbour in New Zealand.


    June 9, 2013 at 4:37 pm

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