460 
STEPHENSON’S PATENT 
across the ends, serving to support the whole engine, which is firmly fixed to it. It is 
made of good tough ash plank, the side pieces N' N' are three inches thick and seven 
inches deep, and covered on both sides with sound wrought iron plates, a quarter 
of an inch thick, fixed on by a number of iron bolts; the best plates are termed 
Low Moor plates. The side pieces are morticed into the end pieces, O' P', of the 
frame; that in front of the engine, O', being five inches thick, and thirteen deep ; 
angle pieces of iron are bolted on to strengthen the corners inside and out. The 
outside length of the frame is 17 feet, and the width 6 feet 4 inches. The boiler, 
fire-box, and smoke-box, are fixed to the side frames, N'N', by strong wrought 
iron stays, u v, four inches and a half wide and half an inch thick. The stays, 
u'u\ for the smoke-box and fire-box, consist of a horizontal piece, (see Plate 
XCII.,) bent downwards at right angles at the inner end, and riveted to the 
side plate of the fire-box or smoke-box, and resting at the other end upon the side 
frame; the other inclined piece is welded on to it at the outer end, the two being- 
bolted down to the frame, and it is riveted like the other piece at the upper end to 
the plate ; the inner ends of both that are riveted to the fire-box and smoke-box 
are made T shaped and twelve inches wide. The stays, v v, for the boiler are made 
and fixed in a similar manner; they are longer, as shewn by the dotted lines in fig. 4, 
(Plate XCII.,) in order to reach the boiler, and have a ring of the same sized iron 
inserted in them, touching the horizontal and inclined pieces of the stays and the 
sides of the boiler, and riveted to each of them. 
Q' Q' Q' are wrought iron plates, seven-sixteenths of an inch thick, bolted on to each 
side of the frame at the axles, and called the axle guides; serving to hold steadily the 
boxes that contain the brasses bearing on the axles, and to guide them when they 
slide up and down from the play of the springs. A piece 4^ inches wide is cut out 
in the middle of each for the axle box to slide in. These axle guides have to resist 
all the strain of the wheels, and those of the driving wheels have to bear the whole 
force of the engine, which is moved along by the axle of the wheels. They are there 
fore strengthened by inch rods, w' iv\ fixed between each of them, with sockets 
across their ends, fitting between the two axle guide plates, and fixed to them by 
bolts passed through both ; the extreme rods are fixed to the end frames of the 
engine, as in Plates LXXXIX. and XC.; the axle guides for the small wheels have 
also bolts fixed through the bottom. 
R' R' R' are the axle boxes in which the axles turn; they are all alike, and are 
shewn to three times the scale, or 2^ inches to a foot, in figs. 38, 39, and 40. 
Fig. 38 is a section along the centre of one of them ; fig. 39 is a cross section; and 
fig. 40, a plan of the top. A A is a cast iron box, open at the bottom and 
the inner side, and 4^ inches wide, so as to fit into the opening in the axle guides. 
A hollow, B B, is cast in the top of the box A A, for the purpose of holding oil to