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there any additional observations you wish to make to the Committee?—There are. I was asked what I had performed, and what was my opinion as to whether Steam power could be made useful on common roads in general, and the difference in effect between broad and narrow wheels on such roads, respecting their breaking up or settling down the surface, and what further advantages I might expect from my late improved Steam Engine. In answer, I beg to say, in 1804 I invented and introduced the high-pressure Steam and locomotive Engines, and also, in 1813, invented the Iron Tanks and Buoys for His Majesty's Navy. In 1814 I was engaged by the Spanish Government to construct in England nine high-pressure Steam Engines, and a mint, with pump-work, and everything complete for draining the great mines of Pasco, in Peru: they weighed 500 tons, in 20,000 pieces, the boilers each of six tons weight, all in single plates, and the cylinders each in six pieces, all carried up the mountains on mules' backs, and put together on the spot, by which the mines were effectually drained, the ores wound up, stamped, smelted, and coined; they remained in full work until the Spanish army retreated through the mines before the Patriots, and on their retreat broke the Engines, and threw them into the Engine pits. For a Report of my progress in Peru, see the first Number of the Geological Transactions of Cornwall, copied from the Lima