The San Francisco call., 1898-05-15

ments from the combination of which these ships derive their distinctive class characteristics.
 He is told that the Indiana is a bat tIe-ship, the Brooklyn an armored cruiser, the Columbia 6 protected cruiser, and the Puritan a monitor. But it is probable that he has only vague idea as to what qualities it is that mark the distinction, or why the distinction should need to exist at all.
 These diagrams and a perspective drawing which show the constructive features of the several types of war ship have been prepared to answer these questions
 In diagrams l to 3 the arnor is in- dicated by full black lines or by shad- ing, the approximate thickness of the armor being shown by the thickness or the lines and the depth of the shading. The fine line represents the unarmored portions or the ordinary plating of the ships. In the perspective view the ar nor is shown by full lines and shading and the ordinary ship plating by dotted lines.
 When the naval architect sits down at his desk to design a warship of a certain size he knows that there IS one element of the vessel which IS hXed and unaIterable, and that is her dis [. the actual weight of the ship, Which IS, of course, exactly equal to the weight of water which she displaces. This to- tai weight is the capital with which the architect has to work, and he uses hls judgment in distributing 1t among the various elements which go to make up the ship Part is allotted to the hull, part 10 the motive power, part to the arrnor protection, part to the fuel, stores, furnishing and general equip ment.
 It is evident that the allotment of weights is a matter of compromise whatever excess is given to one element must be taken from another, else the ship will exceed the given displace- ment Among the elements above mentioned there are some, such as the weight of hull, provisions, stores and furnishings, which for a given size of ship will not vary greatly. There are other elements, such as guns, armor, engines and fuel supply which may vary considerably in different ships, according to the type Of vessel that IS produced.
 signing an extremely fast ship of type No. | which has a SD cd of twenty three knots. he will have to allot such a large amount of weight to the motive power that he will only be able to give the ship very slight armor protection a GOlDDdTdllNGlJ guns If he wishes to produce 1ast ship that shall be more heavily armed and arrnored he has to be content With less speed say tweIfy or twenty-one knots, as in No. 2. and the weight so saved on the motive power appears Tn the shape of a side belt of armor at the water line more complete protection for the guns in the shape or barpettes and turrets and considerably heavier armament f. again, he desires to pro duce a ship capable of contending with the most powerful ships in line of bat tle as in No 3, he is content with much lower speed, say sixteen or seventeen knots an hour, and he increases the power of his guns until they weigh over sixty tons apiece, and pro- tects them with great redoubts and turrets of steel one and a half feet thick, besides protecting his water line in the region of the LngineS and boilers with a belt of steel of the same dimen- sions
 The swift and lightly armed and ar- mored ship is known as protected cruiser; the less speedy but more heav- fly armed and armored ship belongs to the armored cruiser type, and the slow est ship, with it's capacity for taking and giving the heaviest blows that modern guns can inflict, is known as a attle-ship.
 In the construction of warship the two qualities of attack and defense nave to be supplied. The offensive powers are furnished by the guns, tor pedoes etc.
 Now it can readily be understood that all this amount of heavy armor and guns adds greatly to the weight of the ship, and for this reason, in spite of her smaller engine power a first-class
 It will be seen that all that part of