duced. Its projectile was 115 lbs. weight, while the charge was 30 lbs. of powder. The charge of the old 68-pounder was 16 lbs. At 1000 yards there was sufficient energy to penetrate 7 in. of iron. Had armour not increased in thickness, we might have been satisfied with such a capability. But much stouter plates were now being rolled, and the gun had to grow likewise. Ordnance of 9, 12 and 18 tons, all on the principle described, were successively designed and put afloat. The largest of these was charged with 70 lbs. of powder and a projectile weighing 400 lbs. The 9-in. armour of the 'Hercules' had defied the efforts of a 300-pounder, and Sir William Armstrong, in a letter to the Times of June 26th, 1865, said, speaking of a 600-pounder which had then been tried: 'Powerful as this 600-pounder has proved itself to be, I confess I have great doubts of its obtaining the mastery over the "Hercules" target unless the enormous charges already used with that gun be still further increased.' He doubted the possibility of constructing a gun of sufficient strength to penetrate the 'Hercules' target. But hardly had these words been written when heavier guns began to be produced, and we passed on to ordnance of 25 and 35 tons. This was the struggle between guns and armour.
It is not to be supposed that guns of this weight could be carried on board ship without an entire reconstruction of the methods of mounting them. To Captain Scott's iron gun-carriages is due a facility in working these guns which had not in some respects
