Rifled Heavy Minenwerfer Mortar
An illustration showing the German minenwerfer, or mine launcher, class for short range mortars. The mortar weighs around 1693 pounds, and has a rifle length of 4.54 calibers.
Encyclopaedia Britannica (12th ed., vol. 32) (New York, NY: The Encyclopaedia Britannica Company, 1922)
Courtesy the private collection of Roy Winkelman