Among other undertakings he repaired and improved the navigation of the river Calder; he built the bridge over the Tay, at Perth, and some others on the Highland road, north of Inverness; he laid out the line, and superintended the execution of a considerable portion of the great canal connecting the Forth and Clyde. His high reputation was shown shortly after the two centre arches of old London bridge had been thrown into one. The foundations of the piers were discovered to be damaged, and the danger of the bridge was esteemed so imminent that few persons would venture to pass over it. The opinions of the architects on the spot were deemed unsatisfactory; and Smeaton, being at the time in Yorkshire, was summoned by express, to say what should be done. He found that the increased volume of water passing through the centre arch had undermined the piers; and removed the danger by the simple expedient, the success of which he had proved on the river Calder, of throwing in a large quantity of rough stone about them. The interstices of the heap soon are filled up by sand and mud, and the whole is consolidated almost into one mass, and forms a secure and lasting barrier. The best known of Smeaton’s works, after the Eddystone light-house, is the magnificent pier and harbour of Ramsgate. This undertaking was commenced in 1749, and prosecuted for some time with very imperfect success. In 1774 Smeaton was called in; and he continued to superintend the progress of the works till their completion in 1791. The harbour is now enclosed by two piers, the eastern nearly 2000, the western 1500 feet in length, and affords a safe and a much needed refuge to ships lying in the Downs, even of five and six hundred tons, which before, when driven from their anchors by stress of weather, were almost certain to be cast ashore and wrecked. It would be vain to enumerate all the projects in which he was consulted, or the schemes which he executed. The variety and extent of his employments may be best estimated from his Reports, of which a complete collection has been published by the Society of Civil Engineers, in consequence of the liberality of Sir Joseph Banks, who had purchased, and presented them to the Society for this purpose. They fill three quarto volumes, and constitute a most interesting and valuable series of treatises on every branch of engineering; as draining, bridge-building, making and improving canals and navigable rivers, planning docks and harbours, the improvement of mill-work, and the application of mechanical improvements to different manufactures. His papers in the Philosophical Transactions are published separately, and fill another quarto volume. They contain descriptions of those early inventions which we have mentioned, and of an improved air-pump, and a new hygrometer and pyrometer; together with his treatise on Mill-work, and some papers which show that he was fond of the science of astronomy, and practically skilled in it.