The Vickers plate did comparatively well, but its resisting power was far below that of the Schneider plate. this being clearly shown by the greater penetration, and by the less amount of work done on the projectiles. Being much softer than the Schneider plate, it was much less shattered. Its back was bulged out considerably by the first shot, enough to have badly bent any framing behind it. The remaining shot did not cause any great inliging at the back, but, instead, the metal was clipped out around the shot-holes. After the trial, although considerably cracked, it was removed from its backing without having the cracked parts separate. Its lack of homogeneity was shown by the difference in penetration of the last three projectiles-17.21 and 14 in., respectively—all of which remained unbroken.
The Schneider nickel-steel plate did not show up as well as was expected, cracking more than Vickers, but it proved best of all for armor protection. Only two of the projectiles got their points beyond the back of the plate. When removed from the backing, this and the compound plate had to be banded to keep their fractured parts from separating. The relaninding of the projectiles from this plate showed it to be more elastic than the all-steel, the latter acting more like good wrought iron when attacked by projectiles of excellent quality. One especially noticeable feature was time little effect of its many cracks on time penetration of succeeding projectiles. As a result of this trial, Schneider obtained a Contract for' .100 tons of armor for time Russian battle-ship Georgy Pobedonetz, and Vickers an order for 300 tons of steel plates, from 3 to 5 in. thick, for two Russian gunboats.
Time first most important trials in this country were held at. Annapolis in September, 1890, at which three plates were presented, one of steel and one of nickel steel, by Schneider & Co., Crensot, France, and one compound plate by Callum' & Co., Sheffield, England. The plates weighed about 20,800 lbs., and were arranged on chords of a circle, with the gun-pivot as the (inner, and time muzzle of the gun 28 ft. distant from the eenter of the plate toward which it was pointed. The gun used on the first lmy was a 6-in. breech-loading. rifle. 3.5 calibers long. Time charge used was 441 lbs. for each round ; the striking velocity 2.07.5 ft. per second. The projectiles were I loltzer 6-in. armor-piercing shell, weighing 100 lbs. After
four rounds had been tired at each plate. further firing was deferred until an 8-in. gun had been mounted in place of the ti-in. The charge was 8.5 lbs. of brown prismatic powder, the striking velocity being 1,850 ft. per second. The projectiles were Firth armor-piercing shell, weighing 210 lbs.
The compound plate was perforated by all projectiles. and its steel face was destroyed. Two of time shells passed completely through both plate, and backing. Both steel plates kept out all projectiles, the all-steel plate showing slightly greater resistance than the nickel-steel plate; but the former was badly cracked by the 8-in. shell, while the latter remained uncracked.
The hard face of the compound plate was not only easily overcome by the projectiles, but was also nearly all scaled off from the soft wrought-iron back. The ease with which all the projectiles perforated was taken as proof that the plate fell far short of having 50 per cent greater resisting power than a wrought-iron plate of the same thickness. The soft wrought iron back was, however, uncracked at the end of the trial. The effect of the larger projectile was out of all proportion to that of the 6-in., its recovery undeformed proving that all the work was done on the plate. No such great difference, at the corresponding shots, was found with either of the two other plates. A decided disintegration of the metal at each shot was noticed, on account of which successive shots encountered less resistance, as evidenced by the successive greater penetrations.
At the end of the fourth shot at each plate a choice between the steel and nickel steel would have been in favor of the former, on account of the less amount of penetration. Up to this point the steel had proved itself the superior• in resistance to penetration and fracture of any plate ever previously tested. Three of the four projectiles fired at it remained unbroken, which, with the equal amount of penetration in each case, gave unmistakable proof of the homo geneous character of the metal of the plate. Its great elasticity was evidenced by the rebounding of the projectiles, and the manner in which the metal came to the front and heaped up in regular fringes abort the shot-holes.
But the nickel-steel plate gained the day at the fifth round, when the 8-in.
projectile was broken in many pieces, after having forced its point but 104 in.