s. Maudslay Sons & Field,
Lambeth. They were designed to develop 13,000 horses with natural, and
20,000 with forced draught. They consist of four distinct sets of
triple expansion inverted cylinder engines, and occupy with boilers,
etc., nearly two-thirds of the length of the ship. They are placed in
four separate compartments, two sets being coupled together on the
starboard and port sides respectively for driving each screw. There
are four high pressure cylinders, 36 in. in diameter; four
intermediate cylinders, 52 in.; and four low pressure cylinders, 80
in.; with a stroke of 4 ft. Each set of engines has an air pump 33 in.
in diameter and 2 ft. stroke, and a surface condenser having 12,800
tubes and an aggregate surface of 2250 square feet, the length of the
tubes between the tube plates being 9 ft. There is also in each
compartment one centrifugal circulating pump driven by a small
independent engine, of the diameter of 3 ft. 9 in., and capable of
pumping from the bilge as well as the sea. The screw propellers are 18
ft. 3 in. in diameter with a mean pitch of 24 ft. 6 in.

Steam is furnished by six main double-ended boilers, having four
furnaces at each end, and one auxiliary boiler, with a heating surface
of 900 sq. ft., the dimensions of the former being 15 ft. 2 in. by 18
ft., and of the latter 10 ft. by 9 ft. long. The total area of
firegrate surface is 863 sq. ft, and of heating surface 26.936 sq. ft.
Each engine room is kept cool by four 4 ft. 6 in. fans. Forced draught
is produced by twelve 5 ft. 6 in. fans, three being stationed in each
stokehold. The electric lighting machinery consists of three dynamos
of Siemens manufacture driven by a Willans engine, each of which is
capable of producing a current of 400 amperes. The after main engines
can be easily disconnected and worked separately for slow speeds.

The Blake had her steering gear tested on Tuesday, Nov. 17. With both
engines going full power ahead and turning to starboard, with her helm
hard over 35 deg., she completed the circle in 4 min. 40 sec., the
port circle being completed in 5 min. 5 sec. The diameter was
estimated approximately to be about 575 yards. Forty-five seconds were
required to change from engine steering to steering by hand. By manual
gear the helm was moved from midships to hard a-starboard in 40 sec.,
from starboard to hard a-port in 2 min. 10 sec., and from hard a-port
to midships in 2 min. 20 sec. The heavy balanced rudder and