ARMOUR AND ITS ATTACK BY ORDNANCE. 
87 
much more than Tresidder’s. The hard face of the latter performed 
Fig. 17. 
its work completely, breaking up the shot so abruptly that little rend¬ 
ing strain could have been thrown on the plate. The plate, indeed, 
was well supported round its edge and at the back, but it cannot be sup¬ 
posed that such support was called much into play. Harvey’s second 
plate also broke up every shot. It was apparently penetrated far deeper 
than Tresidder’s, but the projectiles were 8-inch ones, and their energy 
much greater, and the test more severe than that of Tresidder’s plate, 
even allowing for the difference in thickness. As above-said, the frac¬ 
ture of the projectiles was effected by the Harvey face, but nofc so 
quickly as to save the plate from a tremendous rending strain which it 
bore admirably, probably owing to its nickel. Tresidder might fairly 
plead that he had defeated the attack of 6-inch Holtzer projectiles 
more completely than the Harvey plate (see p. 59), which allowed the 
