16i NIGH DLLS's SEAMANSHIP AND NAUTICAL KNOWLEDGE

Emergency Steering Gear,—A method of steering the ship alternative
to the steam engine gear has to be provided. This sometimes takes the
form of hand screw gear, as already described, mounted over the rudder
head and geared into the crosshead by dropping in bolts. It is impracti-
cable to steer large vessels satisfactorily by hand gear, so usually two
steering tackles are kept ready at hand, one for each side. One block
of the tackle is shackled to the end of the qua&rant and the other block to
a ringbolt directly forward of it, the hauling part being led to the barrel
of a winch in substitution of the steering chains. Eefer to the poop
plan of Caledonian Monarch and note the rudder brake on the after
side of the quadrant to hold it in position in the event of a breakdown,
also that the small inner barrels of the shaft of the winch are intenaed
for the hauling part of the steering tackles (Fig. 23).

Fig 28.—-Steam Capstan.
The chief "officer is responsible for the working of deck machinery,
but repairs and maintenance are carried out by the engine-room staff.
Steam winches are primarily for handling cargo and incidentally for
warping the ship alongside piers. They may be either spur-geared or
friction-geared, the latter type being designed for quick operating.
The Clutch Winch is employed for quick lowering/ The gear wheel
is driven by a pinion clutched to the crankshaft, and when the load
is raised to the desired height the winch is stopped, the strap brake
applied to the drum and the clutch thrown out of gear thus putting the
load, when being lowered, under the control of the brake..
The Link Motion Gear is usually adopted for cargo winches* The
load is lowered by putting the winch into reverse gear so that the load