Believing that the advantages of projectiles of great size, carrying a very large bursting charge, could be better illustrated by a gun of extraordinary caliber, I designed a cannon having a caliber of twenty-four inches, but having a weight of only 43 tons, the weight and length of the gun being the same as the British 12-inch 43-ton gun. This gun was designed to throw a semi-armor-piercing projectile weighing 1,700 pounds, and carrying an explosive charge of 1,000 pounds, the total weight of the projectile being 2,700 pounds. While the projectile was not designed to pierce heavy armor, it was capable of penetrating the decks and sides of light-armored cruisers and deep into earth or concrete for the destruction of forts. It was a veritable aërial torpedo. By means of the special form of multi-perforated smokeless powder designed for this gun, the huge projectile could be thrown to a distance of nine miles with the gun at maximum elevation, and still with a comparatively low chamber pressure. The projectile was provided with a safety delay-action detonating fuse, designed to explode it after having penetrated the object struck, thereby securing the maximum destructive effects. It is reported that the Germans have made a huge howitzer weighing 45 tons, having a caliber of 23-1/2 inches, which also is capable of throwing a projectile weighing more than a ton to a distance of nine miles. The drawings used in my lecture were published in the _Journal of the Royal United Service Institution_, April, 1898, and re-published in many scientific and engineering magazines, and in newspapers both here and abroad. The descriptions of this gun and projectile were illustrated, as was the manner of its employment for the destruction of the kinds of forts destroyed by the Germans at Liège and Namur. The use of high explosives in big armor-piercing projectiles is now universal, but on the publication of my lecture in 1897 I was subjected to much criticism, especially in some of the London newspapers, whose editors took issue with me as to the practicability of throwing large bursting charges of high explosives from high-power guns. Prior to that time the only success achieved in throwing large charges of high explosives was by use of the Zalinski pneumatic dynamite gun, a battery of which had been made and mounted at great expense at Sandy Hook. These air-guns imparted a maximum velocity of only about 600 feet per second to the projectile. The maximum charge was 600 pounds of nitro-gelatin. The projectile had no penetrating power whatsoever, and was designed to go off on impact. My proposition to throw large charges of a high explosive from a big gun, at high velocity, using a propelling charge of gunpowder, appeared to many to be a very hare-brained intention indeed, to say nothing of shooting it through armor and exploding it behind the plate.