National Geographic : 1917 Apr
of industry involved in the casting, turn ing, and assembling of these various types of cannon. Special ma chinery must be em ployed in each in stance where there is a variation in caliber. Complete foundries are given over to the manufacture of the separate parts of the gun and gun carriage. The industrial organi zation for one size of gun alone is greater today than the total pre-war ordnance or ganization. THE 20-INCH CANNON OF FRANCE From the failures of the Germans the French found that the problem of heavy ar tillery in the field was transportation; so French artillery ex perts began at once to try to solve this diffi culty. They have suc ceeded in their task. Their triumph is the construction of a rail road truck upon which is mounted a 20-inch cannon, the heaviest piece of artillery in the world. The marvelous man ner in which the French have overcome the mechanical diffi culties that hitherto confined heavy artil- THE SHOWER BATH Judging by this contraption, the French soldier has developed a modicum of Yankee ingenuity. A water-wheel motor operates a hydraulic lift, which supplies a bucket reservoir with the "makings" of a sprinkle. The apparatus works, but it looks as if it might have been modeled after a comic cartoonist's distorted dream. lery to fortress or siege operations is a striking example of what French brains are doing in this war. Firing a 12-inch gun from a foundation built along a spur of railway was consid ered a mechanical impossibility before General Joffre's expert artillerists dem onstrated the success of the idea. It was not only in the construction of these guns that France showed her skill, but in their operation. French gunners first developed indirect fire-the art of hitting an unseen target-and in this war they have brought indirect fire to tech nical perfection and even applied its prin ciples in new ways. Undoubtedly, in accounts of present-day battles in Europe, the reader has met the phrase curtain or barrage fire. He may have guessed something of the nature of this artillery expedient.