The engines of those early steamboats were, as a rule, a sort of beam engine. The famous _Comet_ was engined in that manner. John Robertson, who actually set up the _Comet’s_ engines, lived to place them subsequently in South Kensington Museum. A beam, or lever, which worked on a pivot at its centre, was placed between the piston on one side, and the connecting rod—which was fastened to the crank—on the other. Thus, one end of the beam, or lever, was attached to the piston rod, and the other to the end of the connecting rod which drove the crank and the wheel. A development apparently of this beam-engine arrangement was the side-lever engine—a form of which marine engineers were also fond. The side lever seems, in fact, to have been a sort of double beam engine. The cylinder was placed upright, and a cross-piece was fixed to the end of the piston rod. From either end of this cross-piece a rod was connected with a beam or lever on either side of the machinery below. These levers worked on pivots at their centres, and their other ends were joined by a cross-piece united by a rod to the crank-shaft above. The idea in the side-lever engines appears to have been to obtain equal strength on both sides for each paddle wheel. Marine engineers did not apparently at first grasp the idea of a direct-acting engine—that is, simply one connecting rod between the piston and the crank which pulled round the wheel; perhaps the sizes and arrangements of those early steamboats did not permit of this. But in the development of the locomotive, the direct-acting engine did not appear at once. In any case, even the first vessels of the celebrated Cunard Line were of the cumbrous side-lever type. Now, when Fulton had made his _Clermont_ in 1807, and Bell had put his _Comet_ on the Clyde, some of the English speaking people on both sides of the Atlantic began, we say, to see that there was a future before the new invention. In 1809, the _Accommodation_ ploughed the waters of the great St. Lawrence, and two years later a steamer startled the dwellers on the mighty Mississippi. The _Elizabeth_ also followed the _Comet_ on the Clyde in 1813. She was bigger than her predecessor, but only of thirty-three tons; she was fifty-eight feet long, and her engine of ten horse-power. She was built by the constructors of the _Comet_, Wood & Company, of Port-Glasgow, under the direction of Mr. Thompson, who had been connected with some of Bell’s experiments.