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 the speed of the ship throwing great labor upon the crew manning the wheels, the hand gear was afterward disconnected and the connection with the steering engine completed in 40 sec.

[Illustration:  THE NEW BRITISH CRUISER BLAKE]

On Nov. 18, when the vessel went on speed trials, the draught of the vessel was 24 ft. 8 in. forward and 26 ft. 8 in. aft, which gave her the mean load immersion provided for in her design.  There was a singular absence of vibration, said to be due to the space over which the machinery is spread, but perhaps also due, in part at least, to the number of cranks, as the cylinders deliver six throws throughout the circle of revolution.  The results of each hour’s steaming are as under: