We have now to notice the labours of two gentlemen, who are justly cele brated for their ingenuity and skill in mechanical construction, in various departments of art, besides that of locomotion by steam. We allude to Mr. Joseph Gibbs, late of the Kent Road, and Mr. Augustus Applegath, of Crayford in Kent, who had a joint patent, dated 29th March, 1833, for " certain improvements in steam-carriages." To give an intelligible descrip tion of the many original contrivances contained in their elaborate specification would, with the requisite illustrations, require five or six of our pages ; we must therefore be content with giving an idea of the nature of the subjects, and refer the curious reader (for the present) to the enrolled parchmen ts.
The first described improvement relates to the general arrangement of a steam-carriage. The boiler is of a very novel description, and consists of a series of double cones arranged one over the other, the external angles or spaces between which are receptacles for water, which is circumscribed externally by a cylindrical casing. The fire is in the centre of the series of cones, and operates upon their extensive surfaces; and the flue is so arranged as to repeat the heat ing operation by a descending current. There is also a curious combination of shafts, wheels, couplers and springs for varying the speed, &c.
The specification of Mr. Jessop's patent, dated the 31st June, 1833, relates to the manner of constructing the chairs in which the rails 'are fixed; that is, in place of the usual mode of fixing and supporting the chair upon a sleeper, the chair is made distinct from the pedestal, which is attached to the sleeper, and the chair and pedestal are connected by a universal joint or hinge, which permits the pedestal to adapt itself to any irregular sinking of the block or other support on which it rest.), and insures a firm and solid bearing upon its base. The patentee also effects it by the combined motion of a hinge joint, or other means permitting motion between the pedestal and chair, and a movable joint formed at the junction of the chair and rail, so as to produce the same effect, and thereby answer the purpose of a universal joint.
The following drawings represent several methods of constructing the uni versal joint, in all of which r r are the rails, c c the chairs, pp the pedestals, and b b the blocks or sleepers ; jj are junction bars of cast or wrought iron, by which the opposite chairs are connected together, and the rails are thereby held parallel to each other, and at a proper distance apart, and are also retained in a suitable position to insure a fiat bearing on the surfaces of the rails for the wheels to Mae! upon ; s s are cast-iron bed-plates or sleepers, (which may be used to rapport the rails where stone is expensive,) so constructed, that the pedestal may be readily adjusted, by the introduction of a wedge or packing, to a proper level, without disturbing. the seats which the bed-plates may have acquired on the ground ; the same method of construction being applicable to thepedestals, when they are attached to stone blocks.
Aga. 4 and 5, are sections of the pedestal and chair, showing an orbicular universal joint, by means of which the pedestal adapts itself to any irregular sinking of the stone block or other sleeper, whilst the connecting or junction bars retain the rails in their propel gauge, and their opposite surfaces in the same plane or straight line.
• Figs. 9 10 and 11, are a side view, plan, and emo tion of a cast-iron bed-plate, used as a substitute for the stone blocks ; showing also the method or adjusting the rails by means of wedges or paokings introduced between thees and the base of the pedestal, which is fit in the recess formed in the bed-plate, and secured laterally by means of a wedge or key. The patentee states his
claim to consist in "constructing railways, to the using el chairs andpedestal', which are capable turning or moving on universal or other similar Joints, as above described, whereby the railway will not be so liable as heretofore to be deranged by the sinking of the blocks or sleepers, whether of stone, wood, iron, or other material." Until recently the locomotive engines upon the Manchester and Liverpool railway, were usually con structed with a double cranked axis upon the two main wheels of the carriage, which wheels were provided with flanges on their peripheries to keep the engine on the rails. But this mode of construction has been found to be defective, owing to the liability of the crank axis becoming strained or broken, by the excessive friction of the flanges of the wheels against the rails, when the locomotive is entering sidings, turnings, or crossings of the rails, or 'sassing along curvatures in the line. For it will be evident that the carriage has a tendency at these places to run off the rail sideways; which ten dency is counteracted by the flanges on the wheels bearing laterally against the inside edges of the rails, on the concave side of the curvature; and, when it is considered that the great weight and momentum of the moving body meets with a sudden inflexible resistance at the extreme end of the lever, or peri phery of a large wheel, we may readily conceive its liability to be broken, or at least strained. It is evident that any lateral bending of the cranked axle, although fitr short of a fracture, will, by putting the wheels out of square, pro duce a violent surging motion of the whole engine sideways in its further pro gress along the rails ' • and such violent action must be very liable to break the cranked axle, or run the engine off the rails. To obviate these disadvantages, Mr. Robert Stevenson (under his patent dated 7th October, 1833), divests the tires of the main impelled wheels of their flanges, and in lieu thereof, employs two small additional wheels with flanges behind the former. These additional wheels are applied beneath the fireplace end of the boiler, for keeping the engine straight on the rails in its progress forwards; and the axles of these wheels being straight, and, consequently, stronger than the cranked, are not liable to be broken or bent, as experience has proved with respect to the axles of the fore wheels, which are precisely the same. In the following cuts are exhibited a side elevation, an end elevation, and an end section of one of Mr. R. Stevenson's improved engines, in an of which figures the same letters of refer ence indicate correspending parts, though dMrently viewed. 1E, 1E, are the main impelled wheels on the cranked without any projecting flanges on the tires, which run on the edge rails L. M M are the additional small wheels with flanges, applied beneath the hinder or Pomace end of the boiler; and 0 are the ordinary small wheels with flanges beneath the chimney end of the boiler, where the working steam cylinders are situated. The mall wheeh, 0 and M, with flanges, as before observed, keep the engine straight upon the rails ; and the large impelled wheels 1E, have only to advance the engine for and to bear a due proportion of the weight, without having any thing to do with keeping the engine on the rails ; therefore the cranked axle is liberated from all lateral shams, which is wholly transferred to the small wheels 0 and M, with flanges, which, having a straight axle, are capable of sustain ing it.