The portion marked A represents the lower part. The new mode of constructing this carriage is the doing away with the bent futchells and using puncheons in their places. The inside front-stay is forged in one piece; in the centre is formed the socket to receive the king or perch bolt. The stay rests on the top of the two puncheons. There is a =T= plate formed solid with these stays running back to the bed, and at C forms the inner part of the socket for receiving the shafts. The back-stay passes around under the puncheons, crossing the bed to the front and bolted where the front-stay crosses the puncheons, the other end extending to the front, forming the outside of the socket for receiving the shafts. C C represents a piece of hickory bolted between the two stays. The following dimensions applicable to the figure may be useful:—Springs 1½ inches thick, consisting of four plates 37 inches long, 11½ inches opening, which maybe varied to suit the body of the carriage they are intended for. Lower bed 1¼ by 1⅛ inches; ⅜ inch plate on the bottom. Wheel or stay-iron ½ inch round, increasing the size to the puncheons. The box clips over the bottom bed with clip bars, which are worked solid. The clips are put on from underneath the springs, and are secured by nuts on the top. The size of the half-wheel iron is 1 inch by ½ inch. The portion of the figure marked B gives the upper portion of the fore-carriage. [Illustration: Fig. 30.] Fig. 30 shows a fore-carriage with open futchells. A A is where the stiff bar detaches to receive the shaft of the drop poles, the futchells extending to A A. The wheel-iron or stay on the outside of the futchell extends ahead 5½ inches, and also the plate on the inside of the futchells the same distance. These irons require to be a good thickness and tapering to the end. The blocks are fitted on to this space and scrolled at the end. The dimensions given for Fig. 29 will apply to this, and it is used for the same light vehicles, only that a pair of horses are used instead of one. [Illustration: Fig. 31.] Fig. 31 shows an arrangement adapted for hard service. With this kind of wheel-plate we get a good bearing when it is turned under the body. These are made solid, with a plate on the two beds. A is the perch bolt. CHAPTER X. IRON AND METAL-WORK GENERALLY.—LAMPS.—PRINCIPLES OF COMBUSTION. In addition to the foregoing, a large quantity of expensive ironwork is used in the construction of carriages; the principal cause of which expense is not the cost of the material, but the highly skilled labour which is necessary in preparing it.