59

Steam Navigation.

been employed in the construction of Miller’svessel, tried a boat propelled by steam on theForth-and-Clyde Inland Navigation : this, how-ever, was shortly laid aside, on account of theinjury with which it threatened the banks of thecanal, from the violent agitation produced by thepaddle-wheels.

Mr. Symington’s mode of connecting the pis-ton and paddle-wheel, was by placing the cy-linder nearly in an horizontal position, so that bythis means the necessity of employing a workingbeam was avoided. The piston was also sup-ported in its ,posit ; or by friction wheels, sLnd com-municated, by means of a rod, with a crank con-nected with the wheel, which imparts a motionto a paddle somewhat slower than its own. Thepaddle-wheel was placed in the middle of the boattowards the stern, and on this account it becamenecessary to have a double rudder, connected byrods, which were moved by a winch placed at thehead of the boat.

Mr. Symington also employed stampers placedat the head of the boat, for the purpose of break-ing the ice on canals; and this plan, we believe,was also adopted in the original construction ofthe vessels intended for the Arctic expedition.

In 1795 , a very ingenious apparatus was in-vented by Lord Stanhope, and tried by that no-bleman in Greenland Dock. In this experiment,the paddles were made to resemble the feet of aduck, and were placed under the quarters of the