The character of George Stephenson was in every way admirable. Simple, earnest, and honorable; courageous, indomitable, and industrious; humorous, kind, and philanthropic, his memory will long be cherished, and will long prove an incentive to earnest effort and to the pursuit of an honorable fame with hundreds of the youth who, reading his simple yet absorbing story, as told by his biographer, shall in later years learn to know him.
After the death of his father, Robert Stephenson continued, as he had already done for several years, to conduct the business of building locomotives, as well as of constructing railroads. The work of locomotive engine-building was done at Newcastle, and for many years those works were the principal engine-building establishment of the world.
Fig. 57.—Stephenson’s Locomotive, 1833.
After their introduction on the Liverpool & Manchester road, the engines of the firm of Robert Stephenson & Co. were rapidly modified, until they assumed the form shown in [Fig. 57], which remained standard until their gradual increase in weight compelled the builders to place a larger number of wheels beneath them, and make those other changes which finally resulted in the creation of distinct types for special kinds of work. In the engine of 1833, as shown above, the cylinders, A, are carried at the extreme forward end of the boiler, and the driving-wheels, B, are coupled directly to the connecting-rod of the engine and to each other. A buffer, C, extends in front, and the rear end of the boiler is formed into a rectangular fire-box, D, continuous with the shell, E, and the flame and gases pass to the connection and smoke-pipe, F, G, through a large number of small tubes, a. Steam is led to the cylinders by a steam-pipe, H H, to which it is admitted by the throttle-valve, b. A steam-dome, I, from which the steam is taken, assists by giving more steam-space far above the water-line, and thus furnishing dry steam. The exhaust steam issues with great velocity into the chimney from the pipe, J, giving great intensity of draught. The engine-driver stands on the platform, K, from which all the valves and handles are accessible. Feed-pumps, L, supply the boiler with water, which is drawn from the tender through the pipes, e, f.
Fig. 58.—The Stephenson Valve-Gear, 1833.
The valve-gear was then substantially what it is to-day, the “Stephenson link” ([Fig. 58]). On the driving-axle were keyed two eccentrics, E, so set that the motion of the one was adapted to driving the valve when the engine was moving forward, and the other was arranged to move the valve when running backward. The former was connected, through its strap and the rod, B, to the upper end of a “strap-link,” A, while the second was similarly connected with the lower end. By means of a handle, L, and the link, n, and its connections, including the counterweighted bell-crank, M, this link could be raised or depressed, thus bringing the pin on the link-block, to which the valve-stem was connected, into action with either eccentric. Or, the link being set in mid-gear, the valve would cover both steam-ports of the cylinder, and the engine could move neither way. As shown, the engine is in position to run backward. A series of notches, Z, into either of which a catch on L could be dropped, enabled the driver to place the link where he chose. In intermediate positions, between mid-gear and full-gear, the motion of the valve is such as to produce expansion of the steam, and some gain in economy of working, although reducing the power of the engine.