The Eddystone rocks, in the English Channel off Plymouth, were a considerable danger to shipping in the seventeenth century. The Eddystone reef lies fourteen miles south-west of Plymouth. Most of the reef is submerged, with just three feet of rock protruding at high tide. The gneiss rock is rust-coloured and even on the calmest days, water is thrown into the air in spouts. Plymouth had a wide, sheltered bay, a naval dockyard and a booming trade, yet merchant captains were so afraid of being wrecked on the Eddystone, that sometimes they ran around on the Channel Islands or the French Coast trying to avoid it.

In 1698 Henry Winstanley succeeded in building a lighthouse on one of the rocks, and although secured to the rock by iron anchorage bars, the Winstanley structure was washed away in the hurricane of 1703. A second structure was put in place by John Rudyerd in 1708. The Rudyerd lighthouse was more securely attached, but it was built of timber, and it was destroyed by fire in 1755.

( Img: www.lindahall.org/events_exhib/exhibit/exhibits/civil/eddystone.shtml)

The third, and the most famous, Eddystone Lighthouse was completed by John Smeaton in 1759. It was made entirely of interlocked Portland stone, and took two years of work under the most difficult of conditions in the stormy channel.

The illustrations of the completed lighthouse are from Smeaton?s own account of the construction effort, published in 1791.

Smeaton, John (1724-1792)
A Narrative of the building and a description of the construction of the Edystone Lighthouse with stone. London: Printed for the author by H. Hughs, 1791.

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Before the building of the first lighthouse, the reef was an ever present danger to shipping, especially to those making for Plymouth, with as many as 50 ships a year being wrecked, with a high loss of lives.

In 1690 King William III established what is now Devonport Naval Dockyard and decided that a lighthouse should be built to mark this deadly reef. The King commissioned Henry Winstanley to design and build what was to be the first lighthouse in the world to be built in such an exposed position.

Work started in July 1696 and was completed in November 1698. Constructed of wood, it suffered heavy weather damage and had to be virtually re-built the following spring. This second light lasted for four years until 1703 when England was hit by a violent hurricane which swept away the lighthouse, along with the keepers and Winstanley himself, who was visiting at the time.

These early lighthouses were very ornate when compared to the later ones. The third tower was built by John Rudyerd during 1708-9, using shipbuilding principles. He made it narrow and tapering to offer less resistance to the sea and ballasted the base with stones to give it stability, with a ships mast through the centre for flexibility. It was then sheathed with planks which were caulked with oakum and pitch to make it all watertight.

Compared to Winstanley’s towers , this one was very functional and very much more streamlined. This light lasted for 47 years until it burned down one night when the candles in the lantern set fire to the roof. The three keepers were rescued the next morning all suffering from severe burns caused by the wood and molten lead from the roof. One keeper was hit in the face by molten lead and claimed to have swallowed some. Sadly no none believed him at the time, but after his death, 12 days later, an autopsy was performed and 7 ounce piece of lead was found in his stomach!

The fourth tower took three years to build, from 1756 to 1759, and its designer, John Smeaton, used radical new design principles. It was constructed of granite blocks, with dove tail joints held together with quick drying cement of his own invention. So effective was this method of construction it was to become the standard for lighthouse builders world wide. Like its predecessors, candles were originally used for the lantern, until in 1810 they were replaced by Argand oil lamps and reflectors, which gave the equivalent of 3,216 candles.

Smeaton's Tower - now a landmark on Plymouth Hoe
copyright Sue Davis 2004
Smeaton’s tower lasted for 127 years until the rock on which it was sited started to show signs of stress from the action of the sea and fissures started to open up in it. On completion of the current tower, the people of Plymouth raised the money to have it dismantled down to its base and re-erected on Plymouth Hoe, where it still stands today, a tribute to Smeaton’s brilliant design.

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This meant that the stonework in Smeaton’s tower formed an interlocking 3D jigsaw, giving the tower great strength. This technique was called dovetailing (after the shapes carved out of each stone for them to fit together) and was often used in wooden constructions, but until that point, never in stone. The only imperfection in this design was that each layer of rings (course) needed to be held together by small oak pins (trenails). Other than this, the principles for lighthouse design were made.

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The foundations and facing were constructed from local granite. To bond the granite Smeaton invented a quick drying cement, 'hydraulic lime' (a form of concrete that will set under water) it is a formula that is still used today. An ingenious method of securing each block of stone to its neighbour, using carefully cut interlocking joints and marble dowels was employed. Of course the technology for assembling such a structure was of it self, a huge engineering challenge.

To enable the transportation of the large granite blocks from the vessel to the rock a device was designed by Smeaton that is still in use today by ships at sea to enable them to lift to considerable heights. The design that he created has never been improved upon. The combined result of these and other innovations enabled the completion of the tower within three years. Engineering of such a quality in the days of candle power seems all the more extraordinary. 24 candles were used to provide light on 16 October 1759.

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While in use, Smeaton's lighthouse was 59 feet (18 metres) in height, and had a diameter at the base of 26 feet (8 metres) and at the top of 17 feet (5 metres). It remained in use until 1877 when it was discovered that the rocks upon which it stood were becoming eroded—each time a large wave hit the lighthouse it would shake from side to side. Smeaton's lighthouse was largely dismantled and rebuilt on Plymouth Hoe, in the city of Plymouth, as a memorial. The foundations and stub of the old tower remain on the Eddystone Rocks. The foundations proved too strong to be dismantled so the Victorians left them where they stood (the irony of this lighthouse is that although the previous two were destroyed, this one proved to be stronger than the rock upon which it was built and could not even be intentionally taken apart).

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Smeaton's Tower, the old 1750's Eddystone lighthouse was dismantled and rebuilt on The Hoe in 1882. The Georges would have been able to look out to sea and see this lighthouse in action.Smeaton modelled his design on the principle of an oak tree and its need to bend in the wind.1493 blocks all dovetailed together like the rings of a tree and this tower does bend in the wind, that's how it has survived the force of the south-westerly gales. John Smeaton also invented quick-drying cement which was probably quite useful too.

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using dovetail joints and marble dowels. (wikipedia)

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porpoise: marsopa

porgy:

meaton’s Tower 1759 - 1882
After experiencing the benefit of a light for 52 years, mariners were anxious to have it replaced as soon as possible. Trinity House placed a light vessel to guard the position until a permanent light could be built. In 1756 a Yorkshireman, John Smeaton, who had been recommended by the Royal Society, travelled to Plymouth on an assignment which was to capture the imagination of the world. He had decided to construct a tower based on the shape of an English Oak tree for strength but made of stone rather than wood. For such a task he needed the toughest labourers, and many of the men employed had been Cornish Tin Miners. Press ganging had become a problem amongst the workforce, so to ensure that the men would be exempt from Naval Service, Trinity House arranged with the Admiralty at Plymouth to have a medal struck for each labourer to prove that they were working on the lighthouse.

Local granite was used for the foundations and facing, and Smeaton invented a quick drying cement, essential in the wet conditions on the rock, the formula for which is still used today. An ingenious method of securing each block of stone to its neighbour, using dovetail joints and marble dowels was employed, together with a device for lifting large blocks of stone from ships at sea to considerable heights which has never been improved upon. Using all these innovations, Smeaton's tower was completed and lit by 24 candles on 16 October 1759. In the 1870's cracks appeared in the rock upon which Smeaton's lighthouse had stood for 120 years, so the top half of the tower was dismantled and re-erected on Plymouth Hoe as a monument to the builder. The remaining stump still stands on the Eddystone Rock.

( Img://news.bbc.co.uk/2/hi/uk_news/213060.stm)