The next attempt to construct locomotive carriages for the common road, was by the late Mr. David Gordon, whose patent was dated the 18th of December, 1824. The means proposed by this gentleman for propelling, was a modification of the method invented by Brunton, and described at page 399. But instead of the propellers being operated upon by the alternating motion of the piston rod, Mi. Gordon contrived to give them a continuous rotatory action, and to apply the force of the engines in a more direct manner. The following cut affords an external view of one of Mr. Gordon's designs, in which the patented mechanism is introduced. The carriage ran upon three wheels; one in front to steer by, and two behind to bear the chief weight. Each of the wheels had a separate axle, the ends of which had their bearings upon parallel bars, the wheels rolling in a perpendicular position. This arrangement, by avoiding the usual cross axle, affords an increased uninterrupted space in the body of the vehicle; and was the subject of an antecedent patent granted to Mr. Gordon.
In the fore part of the carriage were placed the steam engines, consisting of two brass cylinders, in a horizontal position, but vibrating upon trunnions : the piston-rods of these engines gave motion to an eight-throw crank, two in the middle for the cylinders, and three on each side, to which were attached the propellers ; by the revolution of the crank, these propellers or legs were succes sively forced outwards, with the feet of each against the ground in a backward direction, and were immediately afterwards lifted from the ground by the revolution of another crank, parallel to the former, and situated at a proper dis tance from it on the same frame. The propelling-rods were formed of iron gas tubes, filled with wood, to combine lightness with strength. To the lower ends of these propelling-rode were attached the feet, of the form of segments of circles, and made on their under side like a short and very stiff brush of whale bone, supported by intermixed iron teeth, to take effect in case the whalebone failed. These feet pressed against the ground in regular succession, by a kind of rolling, circular motion, without digging it up; and it must be acknowledged that Mr. Gordon, in these contrivances, succeeded in avoiding the injurious effect upon the road that would otherwise have been caused by this mode of propelling. The guide had the power of lifting these legs off the ground at pleasure, so that, in going down hill, when the gravity was sufficient for propul sion, nothing but a brake was put into requisition to retard the motion, if necessary. If the carriage was proceeding upon a level, the lifting of the pro pellers was equivalent to the subtraction of the power, and soon brought it to a stoppage ; and in making turns in a road, the guide has only to lift the pro pellers on one side of the carriage, and allow the others to operate alone, until the cure is traversed.
The following engraving represents a side elevation of the machine. a the end of the boiler; b the flue ; c an apartment for the engineer to attend the fire and regulate the machinery, which apartment contains a store of water, coke, &c. ; d external connecting-rod (one on each side of the carriage), that actuates the driving cranks of the propellers to the small lifting cranks within the carriage ; a being the axis of the driving cranks, and f the axis of the lifting cranks; g the apartment for the inside passengers, which has glazed windows in front; A the seats for the outside passengers; i the conductor, who guides the carriage by means of four cross levers, turning a small toothed pinion, that works a toothed sector, fixed on a circular frame; pp propellers, of which the whole six are brought into view; s s straps by which the propellers are lifted from the ground. In the experiments that were made with this carriage on
the common road, the feasibility of this mode of propulsion was proved, but the steam power provided was found to be inadequate to produce the required velocity of motion and the patentee, we believe, becoming afterwards con vinced that the application of the power to the running wheels (as insisted on by Trevithick in 1802) was fully effective, and therefore preferable in many points of view, the project was given up.
The next invention in the order of time that presents itself to our notice, is one possessing considerable originality ; and though it Las not bean carried into effect, it contains some ingenious and amusing suggestions, that have formed the groundwork of subsequent inventions.. It is the subject of a patent granted to William Francis Snowden, of Oxford-street, London, on the 18th of December 1824, for a " new invented wheel-way and its carriages for the conveyance of passengers, merchandise, and other things, along roads, rails, and other ways, either on a level or inclined plane." The specification describes the invention under two distinct heads ; the first, as respects the wheelway, explains it as consisting of a hollow trunk with a platform of iron on the top for waggons or other carriages to roll upon ; inside the trunk is placed a machine, called by the patentee a mechanical horse, to which is con nected a toothed wheel, that is made to revolve in a horizontal plane, and to take into the teeth of a horizontal straight rack fixed on one side of the hollow trunk. The vertical axis of the horizontal toothed wheel passes through a lon gitudinal opening in the wheel-way ; above which it is connected to a locomo tive steam-engine, and is actuated thereby ; through the medium of bevil geer the motion thus communicated to the latter by the engines, is applied by the vertical axis to the horizontal wheel of the mechanical horse, inside the hollow trunk ; and as the horizontal wheel is geered into the toothed rack, which is fixed on one side of the trunk, the mechanical horse of necessity moves forward with the same velocity as the horizontal wheel is made to revolve by the power of the engine. Those to whom our literal description may not be clear, will understandit by the annexed figure, which affords a longitudinal section of the mechanical horse, and the hollow trunk or wheel-way. a is a vibrating cylin der, and b the boiler of a locomotive engine, by which the bevil geer c d is actuated, and through the medium of the vertical axis e, the horizontal toothed wheel/ which takes into a toothed rack g ; the mechanical horse h is made to advance in its course, and to take with it the engine and the train of waggons that may be in connexion. w w is the wheel-way, and t t the hollow trunk. As the top of the wheel-way is supposed to be flat, and the carriages without lateral flanges to their tires, it is proposed to guide the carriages by means of tongues like that at i, which enters the longitudinal aperture, and which may be provided with an antifriction roller to prevent lateral rubbing. The inventor proposes to adopt a similar arrangement to the foregoing for the towing of barges, by erecting his patent wheel-ways by the sides or banks of canals and rivers.