frames. The trailing wheels are fitted with a brake as shown.

[Illustration: LOCOMOTIVES FOR ST. GOTHARD RAILWAY.]

The valve motion is of the Gooch or stationary link type, the radius
rods being cranked to clear the leading axle, while the eccentric rods
are bent to clear the second axle. The piston rods are extended through
the front cylinder covers and are enlarged where they enter the
crossheads, the glands at the rear ends of cylinders being made in
halves. The arrangement of the motion generally will be clearly
understood on reference to Figs. 1 and 2 without further explanation.

The boiler, which is constructed for a working pressure of 147 lb. per
square inch, is unusually large, the barrel being 60.4 in. in diameter
inside the outside rings; it is composed of plates 0.65 in. thick. The
firebox spreads considerably in width toward the top, as shown in the
section, Fig. 5, and to enable it to be got in the back plate of the
firebox casing is flanged outward, instead of inward as usual, so as to
enable it to be riveted up after the firebox is in place. The inside
firebox is of copper and its crown is stayed directly to the crown
of the casing by vertical stays, as shown, strong transverse stays
extending across the boiler just above the firebox crown to resist the
spreading action caused by the arrangement of the crown stays. The
firegrate is 6 ft. 11.6 in. long by 3 ft. 4 in. wide.

[Illustration: ST. GOTHARD LOCOMOTIVES.]

The barrel contains 225 tubes 1.97 in. in diameter outside and 13 ft. 91/2
in. long between tube plates. On the top of the barrel is a large dome
containing the regulator, as shown in Fig. 1, from which view the