Spectacular as was the performance of these huge guns, they were of little military value. The slightest variation in the powder would cause a wide variation of range and they could not hope to hit a target smaller than a large city. All seven guns fired a total of 303 shells in 44 days of bombardment, only 183 of which fell within the city. They killed 256 persons and wounded 620. Far more damage at far less expense could have been effected by dropping bombs from aircraft.
Just as a problem in ordnance, American officers designed a gun 225 feet long which would fire a 400-pound shell of 10-inch caliber. It was estimated that with a charge of 1,440 pounds of powder the shell would leave the muzzle with a velocity of 8,500 feet per second and, if fired at an angle of 55 degrees, would have a range of 121 miles. The shell would rise to a height of 46 miles above the earth and would make the 121 miles in about 4 minutes. The gun was never built, because its military value would in no way be commensurate with its cost of construction and operation. The purpose of the German long-range bombardment was to produce a moral rather than a military effect. The Germans hoped to intimidate the French people by this spectacular performance, and in this they failed completely.
In modern warfare large guns are used either to rain a storm of death upon infantry or to destroy their defensive works. In earlier days the effectiveness of gunfire against a charging enemy was increased by the use of grapeshot. A cannon was thus converted into a gigantic shotgun. But although a wide dispersion of projectiles was obtained the range was very limited. This handicap was then overcome by having the gun fire another gun which would discharge when it had reached the enemy’s lines. In other words, the grapeshot or leaden balls were packed into a shell which was fired like a solid projectile, and this exploded when it struck the target, scattering death broadcast. An improvement on this was the timed shell, which would explode while still in the air and scatter its rain of lead over a wide area. The time fuse of a shrapnel shell must be very delicately adjusted to explode at the desired instant. A train of powder is used which may be short-circuited to give the exact length required for any given distance. The powder is ignited by a cap which is exploded by concussion when the gun is fired. The fuse then burns until it reaches the main charge of the shell. This explodes, bursting the shell open and scattering shell fragments as well as the scores of lead balls with which the shell is packed. Should the fuse fail, a detonating pin is provided which will explode the shell when it reaches the ground. Where the object is to destroy defensive works the shell is charged with a high explosive which is detonated not by a time fuse, but by concussion when the shell strikes its target.