52 AXNTTAL OF SCIENTIFIC DISCOVERY. 



At a subsequent trial, however, when the range was increased from 

 two hundred to eight hundred yards, it was found that the Horsfall 

 gun could not be relied on for accuracy, and in fact could not be made 

 to shoot straight at the latter distance. It was, consequently, for all 

 practical purposes, considered to be a not very effective weapon. 



Other trials of a still more important character succeeded. These 

 were made with a Whitworth rifled breech-loading twelve-pounder 

 field gun of four-inch bore, and a seventy-pounder rifled naval gun ; 

 the object of these trials being principally to test the penetration of 

 Whitworth's flat-fronted hardened shells against armor-plates. Here- 

 tofore, all shells, of every description, fired against armor-plates of 

 moderate thickness, failed to produce the least effect upon them. 

 They have always broken like so many glass bottles, merely injuring 

 the target with the flame of their explosion. So constant and invaria- 

 ble were these results that it was taken as an established fact that 

 vessels coated with two-and-a-half-inch, or even two-inch armor- 

 plates, would suffice to keep out any shell. As it is only shell which 

 is dreaded in naval warfare, the Danish, Prussian, and Russian gov- 

 ernments have each built gunboats covered with two-and-a-half-inch 

 armor, confident that this is ample to protect their crews against all 

 but solid shot. The experiments we are about to note, however, 

 proved the complete fallacy of this theory. The first trial was made 

 with the twelve-pounder, which sent a flat-fronted solid steel shot 

 completely through an iron plate two and a half inches thick no 

 slight result, when we consider the lightness of the projectile. The 

 next trial was made with shell, fired from the same rifled twelve- 

 pounder against a target of two-inch armor-plate, with a backing of 

 oak beams nearly a foot in thickness. The shell, with a bursting 

 charge of one pound and fourteen ounces of powder, passed through 

 both plate and backing, and buried itself in the earth beyond. The 

 next, with a charge of one pound eleven ounces of powder, also 

 passed through the plate, but burst in and shattered the timber back- 

 ing behind. No fuse was employed with these shells, the heat gen- 

 erated by the concussion against the target being sufficient to ignite 

 the bursting charge. These results, unexpected as they were, were 

 far surpassed by those obtained with the seventy-pounder naval gun 

 when fired with shell against a stronger target. This target was con- 

 structed of armor-plates bolted upon an oak frame nine inches thick, 

 attached by a side framing to a back of oak four inches thick, coated 

 over with two-inch wrought iron. The interval between the front 

 and back frames was between two and three feet, the target being 

 intended to represent the side of a ship. The shell weighed, when 

 charged, seventy pounds, and contained two pounds and six ounces 

 of powder. This, fired with a charge of only twelve pounds of pow- 

 der, at the usual penetration range of two hundred yards, passed 

 completely through the four-inch armor-plate and oak backing, and 

 burst inside the frame, shattering it to pieces. This startling result, 

 it vshould be remembered, was obtained, not by a gun of unusual 

 weight or calibre, but with one weighing some fifteen hundred pounds 

 less than the naval smooth-bore ninety-five-hundred-pound gun, and 

 with a charge of powder of only one-sixth the weight of the pro- 

 jectile. 



