166 " NICHOLLS'S SEAMANSHIP AND NAUTICAL KNOWLEDGE

gearing with the lower end of the capstan spindle projecting below the
deck but not shown in figure. The direction of motion and the stopping
and starting of the engine are regulated by turning the vertical
rod, which has a thread cut on its lower end to engage with the short
horizontal lever operating the steam valves. This engine may be
disconnected for warping by hand capstan bars.

The illustrations show the fore part and after part of an Emerson
Walker Patent Quick Warping Direct Grip Windlass (Figs. 29 and 30).

Before starting any deck engine, all drain cocks must be opened
and steam allowed to blow through the cylinders until they are clear of
water. When winches are not in use during frosty weather they must
either be kept running slowly or the steam pipes and cylinders freed
from water.

Hydraulic cranes and electric winches are fitted in some passenger
ships as they are cleaner and less noisy than steam winches.

PROPELLING MACHINERY.

Steam propelling machinery consists of boiler, engine, condenser
with auxiliary machines and fittings.

SMELL

Fig, 31.—Fire-tube or Scotch" Boiler.
Boilers are of two types, the Scotch or fire-tube boiler in which the
fire passes through tubes surrounded by water, and the water-tube