100 ANNUAL OF SCIENTIFIC DISCOVERY. 



the broadside is concentrated in one or two enormous shot, which 

 have momentum enough to go through the armor of any of the 

 broadside vessels of the British navy. 



The most material point of dissimilarity between the turret ships 

 of Capt. Coles and those of Capt. Ericsson is that the sides are not 

 nearly so low in the former as in the monitors, and the armor of the 

 sides and the turrets cannot consequently, with any given displace- 

 ment, be made so thick ; nor would it be possible with safety to re- 

 duce the height of the sides, owing to the turrets being carried on 

 rollers on the lower deck, thus passing through openings in the up- 

 per deck, which it is difficult to keep tight without jamming the tur- 

 rets. The openings to the engine-room are also merely covered 

 with gratings, or are otherwise similarly unprotected. In the 

 monitors, on. the contrary, the turrets revolve upon a metal ring, 

 on the upper deck, and all the openings to the interior of the ves- 

 sel are through the top of the turret, or through shot-proof trunks 

 or pipes, so that even if the deck be washed by the waves, water 

 cannot enter the vessel so long as the deck remains water-tight. 

 Capt. Coles's vessels having been but little tested in actual war, 

 the objections to his system are yet to be proved. On the other 

 hand, the monitors had been found, during a war of unprecedented 

 magnitude, to be both shotworthy and seaworthy ; they were con- 

 fessedly unequalled in their power of penetrating other vessels 

 and of resisting penetration themselves. 



In the monitor " Dictator" there is a single turret, carrying 2 

 Rodman guns, each of 15 inches bore ; the sides of the ship are 

 only 16 inches above the water-line, and are defended by armor 6 

 feet deep and 4 feet thick, 10 inches of this thickness being of iron, 

 and the remainder of oak; the turret is of iron, 24 feet inside di- 

 ameter, 9 leet high, and 15 inches thick ; the vessel tapers to a 

 point at each end, the side armor being continued so as to form a 

 ram both at the stem and the stern ; and by this projection at the 

 stern both the screw and the rudder are effectually protected ; the 

 weight of the shot is 425 pounds, and the charge of powder 60 

 pounds. 



Comparing the destructive and resisting powers of the "Dicta- 

 tor" with an iron-clad like the " Bellerophon," the latter carrying 

 on each broadside 5 guns of 10<| inches bore, beside 2 guns at the 

 bow and 3 at the stern of 7 inches bore, he maintained that none of 

 these guns could pierce the iron turret or low sides of the former, 

 or the deck, composed as it is of oak planks 9 inches thick, cov- 

 ered with 2 inches of iron, and that all the parts of the vessel are 

 equally strong to resist the forces that might be brought to bear 

 against them ; that while the guns of the " Bellerophon " would be 

 powerless against the armor of the "Dictator," even if fired in 

 converging salvos, the " Dictator's " guns would easily pierce the 

 armor of her adversary. 



Even if it were doubted whether it was possible to make heavy 

 vessels, so low in the water as the monitors were, sale at sea, their 

 employment would be none the less necessary for the protection 

 of ports, harbors, and estuaries. Though, in the nautical mind, th< 

 ideas of seaworthiness and height of side are iuuis^olubly asso- 



