Page:The Development of Navies During the Last Half-Century.djvu/165

 then evident that steel projectiles would henceforth be necessary to attack hard armour. From that time up to the present the competition has been between the compound plates and all-steel plates. The latter resist perforation better, while the harder surface of the former is more effective in breaking projectiles, and causing them to glance off if struck at an angle. For very thick armour we have therefore adhered to compound plates, employing steel plates where only a few inches are required. France has hitherto produced the best all-steel plates, but a demand for such an article could no doubt be met by our own manufacturers. Already Messrs Vickers have made steel plates which have behaved most satisfactorily under severe tests. Steel is continually being improved, and its resistance to perforation increased by the admixture of small quantities of nickel, manganese, or other substance. The original object of armour being to keep out projectiles, I believe we shall soon adopt that material which shows a marked superiority in this respect, and steel plates appear to me to be winning the day. If the projectiles hold together—and those of modern steel make appear to stand impact well—it stands to reason that the medium they have to pass through should, from front to rear, offer a strenuous resistance. When the face of a compound plate is pierced, the remainder is no great obstacle to