Eddystone
2 of the 7 encyclopedias on this shelf carry an entry for Eddystone. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
a group rocks, daily submerged by the tide, in the English Channel, 9 miles off the Cornish coast, and 14 S. S. W. of Plymouth Breakwater. The rocks lie in lat. 50° 10 54" N., and long. 4° 15′ 53″ W., and have 12 to 150 fathoms water around. The frequent shipwrecks on these rocks led to the erection of a lighthouse on them by Winstanley in 1696- 1700. It was a wooden polygon, 100 feet high, with a stone base; but the great storm of Nov. 20, 1703, completely washed away this primitive structure. Another lighthouse, built in 1706-1709, also of wood, with a stone base, and 92 feet high was burned in 1755. The next was constructed by Smeaton in 1757-1759. It was built of blocks, generally one to two tons weight, of Portland oölite, incased in granite. The granite was dovetailed into the solid rock, and each block into its neighbors. The tower, 85 feet high, had a diameter of 2634 feet at the base, and 15 feet at the top. The light, 72 feet above the water, was visible at a distance of 13 miles. As the rock on which this tower was built became undermined and greatly weakened by the action of the waves, the foundation of another was laid on a different part of the reef in 1879. The new lighthouse, completed in 1882 by Sir James N. Douglass, is, like its predecessor, ingeniously dovetailed etailed throughout. Its dioptric apparatus gives, at an elevation of 133 feet, a light equal to 159,600 candles, and visible in clear weather to a distance of 17½ miles.
Aiton's Encyclopedia (1910)
ed'di-ston, a name given to three ridges of submerged rock off the coast of Cornwall, England. They are exceedingly dangerous to navigation, and have been the cause of shipwrecks innumerable. Many a gallant ship, returning home to England after a long and perilous voyage, has been dashed to pieces almost within sight of home. In 1700 Henry Winstanley, a public-spirited man, erected there a wooden lighthouse 100 feet high, with a stone base. Three years later builder and lighthouse were washed away. In 1709 a rich silk merchant erected a second lighthouse on much the same plan. It was burned down in 1755. In 1759 a third tower was completed, this time at the expense of the government. It had a diameter of twenty-seven feet at the base and fifteen feet at the top. It was seventy-two feet high. It was built of granite blocks weighing from one to two tons each. They were ingeniously dovetailed together. This lighthouse was undermined by the sea, and was replaced by a new tower in 1882. It has a total height of 133 feet. Its light, having a total strength of 160,000 candle power, is visible on a clear night for a distance of nearly eighteen miles.