MECHANICS AND USEFUL ARTS. 85 



locity of the shot. Sir Charles Napier, of Scinde, was accustomed 

 to say that the smooth bores had not been given a fair chance. There 

 is little doubt of this, and the time will come when the children of a 

 future generation will ask why soldiers were called riflemen, and the 

 answer will be, because the guns were contrived with one defect to 

 compensate for another." 



THE ANGULATED PRINCIPLE OF SHIP-BUILDING AS A PRO- 

 TECTION AGAINST HEAVY ORDNANCE. 



It is well known that if a shield of any kind be struck at an angle 

 or on a slant, the sword or bullet glances off, and the force of the 

 blow is destroyed. Targets in all times have been " sloped " accord- 

 ingly. Shields were made convex, either tapering to a point in the 

 centre, or rounded off at the sides in the form of semi-cylinders. 

 Cuirasses took the same form, sloping away from the middle like the 

 breast of a fowl, so that no shot could strike full upon the plate. To 

 take advantage of this principle, Mr. W. Jones, an English engineer, 

 proposes to construct iron-plated ships with sloping sides ; or, in other 

 words, to use the same armor plates as already adopted, but, in- 

 stead of placing them vertically, so as to present an upright wall of 

 metal, to place them at an angle, so that a sloped face only is offered, 

 like the slant of a parapet. To test this device, some experiments 

 were made in August last (1861), under the direction of the British 

 Admiralty. 



A target, representing the sides of a ship, composed of timber- 

 work twelve inches thick, and covered with iron plates 41 and 51 

 inches thick, was constructed, and fired against with an Armstrong 

 gun, carrying a bolt twelve inches in length and seven inches in di- 

 ameter, and weighing one hundred and ten pounds. The London 

 Times makes the following remarks in regard to the experiment : 



"It happened that everything was- favorable to the accuracy of the 

 experiment. The gun was one of the heaviest in use, throwing a 

 bolt of one hundred and ten pounds, the very kind of projectile 

 which had smashed the Shoeburyness butts into fragments. The fir- 

 ing took place at two hundred yards' distance, and the practice was 

 most perfect. The shots hit the target so truly, that if it could have 

 been penetrated at all they must have pierced it. Six bolts actually 

 struck the armor within a space of twenty-one inches by twelve, and 

 three of these fell within an inch or two of the same spot. Thus the 

 critical test of a succession of blows at the same point was thoroughly 

 applied, and it does not seem, indeed, as if any shield could ever 

 have been battered with more tremendous force. The effect pro- 

 duced, however, was comparatively insignificant. The last shot of 

 all, though lighting just on the track of the others, and giving, as it 

 were, the last blow to the work, failed to penetrate the armor ; and, as 

 a general result, it was found that, though no fewer than sixteen 

 shots had been planted more closely together than could ever be ex- 

 pected under ordinary conditions of practice, the plates were not 

 pierced, nor was the wood-work materially injured. The final shot, 

 says the report, fell on Nos. 15 and 3, carrying away the armor 

 plates in irregular pieces between shots 15, 22, 3, 21, 11, 7, crushing 



