a'a', in the other direction. There are other two smaller springs shewn in the drawing, but, in this case, we suppose there are none. All the buffers will then act direct against the ends, d d and d' d', of the springs. This is a much less complicated mode of application, than the preceding.

A modification of this plan, or, rather, an extension of it, is used upon some railways. Two other springs, ee, ii, are fixed upon the frame, independent of the long transverse springs, and the coupling or dragging chains are fixed to these. The carriages are dragged by those small springs, and the buffers, alone, made to act against the large springs; there being, in this case, no rest at the ends of the large springs, the ends of the rods of the buffers acting directly against the ends of the springs.

And it will be seen, that if rests are used at dd and d' d', and if each of the two springs are fastened together in the middle; that the dragging chains will act upon one large, and both small springs at once. Other modifications of this application of these springs, in the middle of the carriages, might be described, but which the ingenuity of the reader will readily supply. Another modification of this plan, but differently applied, has been, to fix each of the long elliptic springs near the ends of the carriage, or between the first and second cross sheths of the frame, or, indeed, in some cases, in front of the cross sheth; the side frame being, in this latter case, lengthened, to allow for the elliptic projection of the spring. In these two cases, the dragchain is affixed directly to the middle of the spring, and the buffer ends directly to the ends of the spring; and in these cases, the objection of the great length of rods, g'g', pushing against the spring, is obviated.

This apparatus is, however, rather expensive; the springs, rods, levers, and bars of the first carriages, having to bear the resistance of the entire train, require to be very strong; and from the number and lengths of the rods, especially those of the plan in Fig. 6, they are liable to get twisted, and put out of order ; and likewise, when all the carriages are not loaded alike, they will not be all in the same line, and, consequently, the buffer heads will not strike each other in the centre of the buffer, but above, or below, accordingly as they are loaded; and, consequently, the blows being oblique, considerable strains, and twists, will be thrown upon the buffer rods, and render them liable to get out of order.

To obviate these objections, Mr. Bergin, of Dublin, contrived a different kind of apparatus, which has been applied by him, with great success, to the carriages on the Dublin and Kingstown railway. Fig. 7, Plate VI., is a representation of this plan of buffer apparatus.

A A A A, are

plates of sheet iron, three inches apart from each other, three sixteenths of an inch thick, and fastened together by rivets. These plates rest upon turned bearings, on the middle of the axles, and are fixed to the iron frame, c c c c, which rests against, but is not attached to, the framework, and cross sheths, B B B, of the carriage. DDDD, are hollow tubes; part of the framing, c c c c. A strong iron rod, E E, passes from one end of the frame to the other, to the ends of which the buffer heads, F F', are fixed, and to which the dragging chains are also attached. This rod, being turned round, passes through the hollow tubes, D D D D, resting upon the rollers, shewn by the dotted lines at rrrr, by which it moves back and forwards, very freely. Around this rod, the spiral springs, shewn in the drawing at 1, 2, 3, 4, are placed;

these springs rest, or abut against, the hollow tubes, DDDD, not being allowed to pass within them. Two collars at a a, are fastened to the rod, E E, moving with it, and against which the other ends of the springs rest, or are attached. The whole of this apparatus resting on the axles, and not being attached to the frame-work of the carriage, does not partake of the rise and fall of the carriages, when subjected to different loads; the oblong holes, shewn at B B B, in the sheths, allowing the apparatus to move up and down. The buffer heads, and rods, E E, of all the carriages of the whole train, are thus kept in the same line, or parallel with the level of the rails of the railway, the wheels being presumed to be all of the same size. Suppose the carriages dragged forward in the direction of the upper arrow, the collars, a a, compress the springs, 1 and 3, and which, acting against the boxes, D D, and cross frames, B B, gradually put the carriage into motion; and if the carriage is to be moved in the opposite direction, the collars, a a, compress the springs, 2 and 4, which act in a similar manner, to put the carriage into motion. The rod, EE, being attached to the next carriage by the drag-chains, and by similar rods, it will be seen, that the springs of one carriage are entirely independent of the other, the direct resistance of the whole train being upon the rod, E E, and the other connecting rods of the several carriages; the irregularities of motion being compensated by the springs of each of the carriages individually, and all at the same moment, when the velocity is increased. When the motion is diminished, or the train stopped, the concussion, or blow, is neutralised in the following manner :— If the buffer, F, strikes that immediately preceding it, the springs, 2 and 4, are compressed, and the body of

the carriage gradually brought into the change of motion, or state of rest, as the case may be; and the buffer, G, striking against the buffer, F', is met by the elasticity of the same parts of the spring. When the carriage is moved in the opposite direction, or in that of the lower arrow, the action is precisely the same; only that the springs, 2 and 4, are compressed by any increase of velocity, and the springs, 1 and 3, by a dimi nution, or when the train is stopped.

Fig. 8, Plate VI., shews a plan of buffers, by Mr. Blackmore, and applied to the carriages on the Newcastle and Carlisle railway, likewise shewn in Fig. 2, Plate VIII. 1 1, is the side frame of the carriage, and 5 5′ 5′′, 6 6' 6", 7, the cross sheths of the framing. Two cast-iron hollow tubes, a A, are fastened to the cross sheths by bolts. An enlarged cross section of the mode of doing so, is shewn in Fig. 9, Plate VI., 55 being the sheths, and a the tube; the latter is put together in two pieces, as shewn in Fig. 9, for the purpose of inserting the spiral springs. Fig. 8, is a section through the middle of the box, or tube; a rod, в в, and c c, passes through each of these tubes, to which the buffer heads, F and G, are attached; a collar is fixed upon the rods at D and E. When, therefore, the carriage is dragged in the direction shewn by the upper arrow, the spring resting against the end, H, of the tube, gradually puts the carriage into motion; and, if there are other carriages attached to the rod, c, the spring acting against the end, I, of the box, drags the other carriage into motion, and so on throughout the whole train. When the carriage is moved in the opposite direction, a similar action takes place. In the case of a diminution of motion, or when the train is stopped, and the buffer heads are brought into action, the springs, acting against