The two main guns, placed on Krupp’s hydraulic carriages, occupy positions in front and rear, and are protected by stands 0.09 meter thick and 1.60 meters high.  They fire en barbette with a lateral range each of 260 degrees at bow and stern—­i.e., 130 degrees on either of the broadsides.  The weight of the barrel of the gun is 25 tons, that of the steel shell 215 kilogrammes (about 430 lb.), that of the brown powder charge 100 kilogrammes; initial velocity of projectile, 610 meters; penetration, 0.524 meter iron; longest range, 17 kilometers (about 101/2 English miles); range at 15 deg. elevation, 10 kilometers.  The six 15-centimeter guns are placed in a kind of machicouli arrangement in two tiers on each of the broadsides, so that always four guns can fire in the direction of the keel to the front and rear.  The weight of the barrel of the gun is each six tons, that of the steel shells 51 kilogrammes, that of the charge 22 kilogrammes; initial velocity, 610 meters.

The 11 quick-firing guns are partly placed along the broadsides, partly in the masts, of which there are two.  The triple expansion engines, having each a bronze screw of 4.42 meters diameter, with three blades and a rise of 6.3 meters, make with natural draught 105 revolutions, and with forced draught 120.  The pumping apparatus are able to lift in one hour 400 tons of water.  The front boiler room contains a special cylindrical boiler for the working of the electrical apparatus, for hydraulic pumps of the artillery service, for anchor windlasses, ventilators, fire engines, etc.  The whole engines weigh 890 tons.  The bunkers have a capacity for 660 tons of coal, which allows for a run of 4,500 sea miles.

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CLARK’S GYROSCOPIC TORPEDOES.

Figs. 1 and 2 represent, upon a scale of about 1/10, two types of torpedoes, the greatest number possible of the parts of which are made revolvable, so as to render the torpedoes as dirigible as the gyrating motion permits of.

Fig. 1 represents an electric torpedo actuated by accumulators, A A, keyed upon the shaft, and revolving along with the gearings.  At the beginning of the running, the accumulators are not all coupled, but under the action of a clockwork movement which is set in motion at the moment of starting, metallic brushes descend one after another upon the collectors, B, and set in action new batteries for keeping constant or, if need be, accelerating the speed at the end of the travel.

[Illustration:  Fig. 1.]

[Illustration:  Fig. 2.  Clark’s gyroscopic torpedoes.]

Fig. 2 represents an air torpedo proposed by the same inventor.  The air reservoir, C, revolves along with the gearings under the action of the pneumatic machine, D. The central shaft is hollow, so as to serve as a conduit.  The admission of air into the slide valve of the machine is regulated by a clockwork which actuates a slide in an aperture whose form and dimensions are so calculated that the speed remains as constant as possible toward the end of the travel.