suspending and operating the main link. As before stated, this link is
used only for reversing, and is therefore always in "full gear" in one
direction or the other; and the striking feature of the arrangement here
used is that, whether going ahead or backing, there is _no slipping of
the link upon the link block_.

The link itself is of the simplest form, being merely a curved flat bar,
L, in which are two holes, A and B (Fig. 7), by which the link is hung
upon the pins, which project from the sides of the eccentric rods at
their upper ends.

This is most clearly shown in Fig. 8, which is a top view of the
reversing gear. The link block is a socket, open on the side next to the
eccentric rods, but closed on the side opposite, from which projects the
journal, J, as shown in Fig. 9, which is a vertical section by the
plane, XY. This journal turns freely in the outer end of a lever, M,
which transmits the reciprocating motion to the valve, through the
rock-shaft, O, and another lever, N. Connected with the lever, M, by the
bridge-piece, K, and facing it, is a slotted arm, G, as shown in the end
view, Fig. 10. The center line of this slot lies in the plane which
contains the axes of the journal, J, and of the shaft, O.

A block, E, is fitted to slide in the slotted arm, G; and in this block
is fixed a pin, P. A bridle-rod, R, connects P with the pin, A, of one
of the eccentric-rods, prolonged for that purpose as shown in Fig. 8;
and a suspension-rod, S, connects the same pin, P, with the upper end of
the reversing lever, T, which is operated by the worm and sector. The
distance, JO, in Fig. 10, or in other words the length of the lever, M,
is precisely equal to the distance, AB, in Fig. 7, measured in a right
line; and the rods, R and S, from center to center of the eyes, are also