Reported in Scientific American, This Week in World War I: March 6, 1915

World War I was an artillery war. Even as new technology—tanks, airplanes, submarines and poison gas—changed the nature of fighting, it was the power of mass manufacturing that had the most profound effect on the conduct of war. The size and number of artillery pieces brought to bear on the trenches of the front lines on the Western Front was surpassed only by the vast scale of munitions they expended in trying to blast a way through the trench deadlock. Over 60 percent of the casualties in WWI were caused by artillery. This week we look at one of those big guns.

The Krupp works at Essen making a barrel for a 42-cm howitzer. Image: Scientific American, March 6, 1915

The Krupp armaments company made most of the artillery used by the German army. The firm also designed and made the siege guns responsible for the earliest successes of the German army. These huge siege guns were designed specifically for the main purpose of blasting apart the permanent fortifications in Belgium and in northern France: the 42-cm Gamma-Gerät (Gamma device) howitzer and more mobile version of the same caliber, the M-Gerät (M device). These 42-cm guns were loosely referred to as “Big Berthas”; they had an actual caliber of 419 millimeters (16.5 inches) and fired huge shells weighing between 1,600 and 2,000 pounds at ranges of up to eight miles. Apparently only seven of these giant guns (five of the former and two of the latter) were built by the time war broke out, but these few guns more than fulfilled the expectations of their designers. The photoillustration at the top shows the Krupp firm making the barrel of one of these monster howitzers. I don’t know if the description of the manufacturing process that follows is accurate, given that “The Germans have not given out any details regarding this piece” and details even after the war was over are sparse, but nonetheless:

A 42-centimeter German shell that failed to explode, displayed as a trophy by the French. Image: Scientific American, July 17, 1915

“It has long been the practice to forge the gun barrel upon a central mandrel which is inserted in an axial hole through the forging, when it is brought white-hot from the furnace and placed in the hydraulic press as shown in our illustration. The material is squeezed between the mandrel and the press, the ingot being given a slight turn between each squeezing, by means of a chain which passes around the forging and is operated by the gears shown in the upper bight of the chain. Gradually the piece is reduced in diameter and drawn out to proper length, until the desired final size of the rough gun barrel is reached.”

The lower photograph is taken from an issue later in the year. It shows one of the monster 42-centimeter shells that failed to explode: generally, on the Western Front about 15 percent of shells were “duds”. The caption says that it “was accepted as a trophy by the French” and put on display (hopefully after the explosive was rendered inert).

Our full archive of the war, called Scientific American Chronicles: World War I, has many articles from 1914–1918 on armaments manufacturing and artillery during the war. It is available for purchase at