32 YEAR-BOOK OF FACTS. 



the money, I will engage to furnish them with puns and projectiles 

 which shall penetrate the sides of a vessel cased with iron plates 4.^ 

 inches thick at the distance I have named. To show that this is no 

 vain boast, I will explain how it can be done. It has been proved 

 that a 08 lb. shot of wrought iron will penetrate a 44-inch iron plate 

 with facility within the distance of 100 yards, the initial velocity of 

 the shot, being less than 1800 feet a second. Those who know any- 

 thing of the theory of projectile force will be aware that a shot of 

 1701b. weight, striking an object with a velocity of 1100 feet a 

 second, would have a penetrating power quite equal to that of the 

 68 lb. shot, while the general effect of the blow would be enormously 

 greater. That a projectile of 1701b. weight may, without difficulty, 

 be fired with the above-mentioned velocity has been proved beyond a 

 doubt experimentally at Shoeburyness, when, from a rifled gun, an 

 elongated projectile of 1741b. weight was fired with a mean velocity 

 of 1200 feet a second to a distance of 2126 yards, the time of flight 

 being 5'31 seconds ; while the mean velocity of flight in a range of 

 more than 10,000 yards was as much as about 1100 feet a second. 

 According to the ordinary method of calculation, therefore, this 

 shot should penetrate an iron plate at almost any distance within its 

 range with the same facility as would a 68 lb. shot at a distance of 

 100 yards. It would really do so, however, with even greater 

 facility. No iron-cased ship could come within the range of ltuiis 

 similar to the one I have referred to without the risk of destruction, 

 unless, as I remarked, the plates of iron were so thick as to render 

 the vessel an inert floating mass, such as might probably be avail- 

 able for coast defences, but for no other purpose. Vessels of this 

 description, indeed, if armed with the above kind of gun, would 

 probably be the most formidable kind of batteries which could be 

 devised. 



" With respect to the angular plates which have lately attracted 

 some notice, I would observe that their efficiency in preventing the 

 penetration of shot must depend upon the relative position of the 

 guns which are brought to bear against them. If a vessel con- 

 structed with angular plates were opposed to a battery high above 

 the level of the water, or to another vessel which carried her guns 

 high, the object of having the plates in a sloping position would bo 

 defeated." 



ARMOUR FOR SHIPS. 



Mr. A. M. Rbhsxl has patented certain improvements in the 

 construction and arrangement of ships of war. Here th 

 employs Armour in the form of iron or steel plates, or plates of other 



material ; or armour in any other form, backed with timber or UOt, 



or otherwise protected in-board of the ship, upon longitudinal and 

 transverse bulkheads or girders extending upwards from the ship's 

 bottom, or other con veo to the height requisite for the shelter 



ol the gun deck, with or without plating Of any thickness, hud upon 



timber or otherwise protected and strengthened overhead. The armour 



.iry for the protection of the' ship may be phuel wholly on the 



