7-! AXXUAL OF SCIENTIFIC DISCOVERY. 



the most formidable powers can be made as light, as handsome, and 

 as nimble as a pleasure schooner. Xo person, indeed, looking at 

 the Warrior from a little distance, would receive any immediate im- 

 pression of her strength. To get that it is necessary to go on board, 

 to look through her portholes, with sides and splay like those of an 

 old donjon casement, to measure the dimensions of her engines, and 

 to add up the feet of teak and iron consumed upon her sides. A few 

 hundred yards off nothing of this kind is thought of, and the object 

 before the spectator's eyes is simply a beautifully-shaped frigate, 

 longer than others, more graceful, and apparently faster. 



" Our success, then, as far as we can discover, may be said to be 

 complete ; but it is dashed with some unpleasant reflections. The 

 cost of these new vessels is tremendous, and we do not know the 

 worst even yet. Ships require docks, and for the whole of our new 

 fleet we have but one dock available. The French, as usual, have 

 taken the lead of us in recognizing their obligations, and are now 

 constructing several docks of the dimensions necessary for the new 

 vessels. Docks, however, are most expensive works, and it is very 

 hard to make them keep pace with ships. It costs little to lengthen 

 a ship, but a great deal to enlarge a dock. It is more than probable, 

 indeed, that we shall require a new establishment somewhere on a 

 scale adapted to the navies of the age." 



On the Manufacture of the Iron Plates of the Warrior Frigate. 

 The London Engineer furnishes the following graphic description 

 of the process of manufacturing the iron plates for the Warrior frig- 

 ate : 



" The tests which were applied to the plates furnished by the build- 

 ers of the Warrior were of the most trying character. Some plates 

 were fired at with sixty-eight pounders, at two hundred yards range, 

 and were literally cut in halves by balls fired one after another on a 

 line drawn on the surface, each ball striking immediately below its 

 predecessor. Upon some other plates the balls made a circular in- 

 dentation upon the surface, nearly as deep as the plates, exactly of 

 the form of the projectile, and as though a mould had been taken 

 of it in some soft and yielding substance. It was only after repeated 

 trials that it was decided that the plates should be of annealed scrap 

 iron. The labor involved in building up these plates is enormous. 

 In the first instance, small scraps of iron are thrown into the fire, and 

 when in a state of red heat are subjected to severe hammering, under 

 the steam hammer, until the whole is beaten and amalgamated into 

 a solid mass of about half a ton weight. This lump is then placed on 

 the top of a similar mass, the whole made red hot, and hammered and 

 welded together. Repeated additions of this kind are made, until 

 about five tons of metal are thus welded together in one huge, shape- 

 less body. This is then brought to a glowing white heat, and placed 

 under the huge hammer, the thundering blows of which gradually re- 

 duce it into shape. Again and again the enormous slab is put into 

 the furnace, and hammered into one piece of fifteen feet long, three 

 feet wide, and four and one-half inches thick. From ten to a dozen 

 men are engaged in the work of moving these ponderous masses of 

 iron, which are moved about apparently with the most perfect 

 ease. Powerful cranes swing the molten mass from the furnaces to 



