268 
POPULAR SCIENCE REVIEW. 
armour of the breastwork is 11 inches thick. The thickness 
of the side-armour of the Admiral Popoff is from 16 to 18 
inches, the breastwork being protected with 18-inch armour. 
The armour is carried to a depth of 4| feet below the water-line. 
In both vessels the curving deck is covered with armour 2f 
inches thick, this thickness being considered quite sufficient to 
resist shot which must necessarily strike at low angles, as the 
Popoffkas are not intended for the attack of fortresses. The 
two guns in the breastwork are mounted on a platform which 
revolves on a central upright axis ; this axis is hollow, and in 
action the charges for the service of the guns are passed up 
through it. The recoil is regulated and stopped partly by hydrau- 
lic compressors, partly by wedges in the back part of the slides. 
In action or in stormy weather all apertures are closed except 
those within the breastwork. Through these the ventilation of 
the ship is kept up, the air currents being formed by revolving 
fans. A light rail runs round the deck, and there is a bridge 
aft of the breastwork and level with the top of it. The engine- 
room hatchway is under this bridge, and the combings are 
carried up to it, so that it is safe from being flooded by the sea, 
which, from the extremely low freeboard, must frequently break 
over the deck. 
The principal dimensions of the two ships are as follows : — 
Novgorod 
Admiral Popoff 
Ft. 
Ins. 
Ft. Ins. 
Extreme diameter . 
101 
0 
121 0 
Diameter of flat bottom 
76 
0 
96 0 
Depth of hold . . . . 
13 
9 
14 0 
Draught of water | f°r warc * 
13 
13 
2 
2 
12 0 
14 0 
Height of top of breastwork 
above 
the water-line * 
12 
0 
13 3 
External diameter of breastwork 
30 
0 
34 0 
Displacement * . * 
2,490 tons. 
3,550 tons. 
The nominal aggregate horse-power of the six engines is in 
the Novgorod 480, in the Admiral Popoff 640. But the actual 
indicated horse-power is very high, that of the Novgorod at full 
speed being 2,270. The capacity of the coal-bunkers is very 
small ; the Novgorod can carry only 200 tons, the Admiral 
Popoff only 250. The former vessel has a crew of 110, the 
latter of 1 20 officers and men. 
The highest speed ever attained by the Novgorod was 81- 
knots, with an indicated horse-power of 2,270. Her ordinary 
speed is about 6^. These are important figures, for it is on 
these data that the whole question of the efficiency or non- 
efficiency of the Popoffka as a ship of war must depend. We 
