i68 



THE POPULAR SCIENCE MONTHLY. 



sels have, since its organization, been constructed on the other 

 side of the Atlantic. 



The types of war vessels considered by naval authorities to be 

 best suited to the needs of our service may be classed in general 

 terms as battle-ships, armored cruisers, protected cruisers, har- 

 bor-defense monitors, gunboats, torpedo-boats (surface and sub- 

 marine), and rams. The uses and functions of each type differ 

 greatly ; some of the more prominent may be broadly stated here. 

 Taking first the battle-ships, we find them to be, of all the types 

 of war vessels, the most powerful in the feature of offense and de- 

 fense ; they are intended to stand and fight, to give and take blows 

 like giants in a prize ring ; and the reason can be plainly seen when 



we appreciate the fact that an 

 enemy can bring his battle-ship 

 within twelve miles of our large 

 seaboard cities, and there tak- 

 ing up a position of vantage, 

 secure from any attack by land, 

 shell the city ; the only vessel, 

 then, that can dispute posses- 

 sion with him point by point is 

 a ship of similar powers of do- 

 ing battle, however successful 

 an attack by torpedo-boat, either 

 surface or submarine, may be 

 when the conditions are suita- 

 ble. The points, therefore, to 

 be emphasized in the design are 

 protection and armament, or the 

 power to deliver heavy blows 

 with the ability to withstand 

 those of its antagonist; with 

 these must be combined power 

 to enable it to act on the offen- 

 sive, such as speed, endurance, 

 habitability, and form of hull that will insure seaworthiness. 



As a purely harbor-defense vessel the monitor stands pre-emi- 

 nent, the entire hull and battery being protected by armor, and 

 at the same time offering such a small target that it is extremely 

 difficult to hit ; but its military value is very seriously impaired 

 when in a seaway, by the short distance of the guns above the 

 water, it being impossible to use them in a heavy sea. Perhaps the 

 vessels most useful for all-around work are the armored cruisers, 

 as they are intended to have great speed, great endurance, guns 

 capable of coping with vessels inferior only to battle-ships, with a 

 very considerable amount of protection afforded to the hull and 



FIG. 4. IOWA. 



Section through Coffer Dams, etc. 



