The preparation of the stone blocks occupied next winter, and by the spring large numbers were ready and were floated off. In May, 1808, the excavations on the rock were continued, and on the 10th of July the first stone was laid with considerable ceremony. By the last week of November three courses of masonry had been laid. By the end of 1809 the tower had been built to a height of thirty feet, and was almost secure from the fury of the waves. “In his report to the commissioners he stated that he found that the form of slope which he had adopted for the base of the tower, as well as the curve of the building, fully answered his expectations—that they presented comparatively small obstructions to the roll of the waves, which played round the column with ease.” The curve of this tower at the base is much greater than that of the Eddystone. The Bell Rock Lighthouse was completed by the end of 1810, and the light was regularly exhibited after the 1st of February, 1811. Counting to the top of the lantern, it is 127 feet high. It may here be remarked that in many works the credit of designing and building this lighthouse has been given to Robert Stevenson, the resident engineer. Rennie, however, has the only rightful claim to be so considered; he acted throughout as chief engineer, furnished the design down to the pettiest details, settled the kind of stone and other materials to be used, down even to the mortar and mode of mixing it. Another work of great labour and difficulty was the erection of a lighthouse on the Skerryvore Rocks, which lie twelve miles W.S.W. of the Isle of Tyree in Argyllshire, and were formerly the scene of numerous wrecks. The operations were commenced in 1838, the architect being Alan Stevenson, son of the Robert Stevenson who was employed on the Bell Rock Lighthouse. The engineer gave the world a succinct account(57) of the difficulties, dangers, and successful issue of the undertaking. [Illustration: LIGHTHOUSE ON THE INCHCAPE ROCK.]