One day grew to be very much like another in that deadlock of pythons. A play for position here was met by a counter-thrust in another place. German inventions were outmatched and outnumbered by those coming from the Allied side. Trench warfare became the daily life of the men. They learned to fight and live in the open. The power of human adaptation to abnormal conditions was never better exemplified than in those weary, dreary years on the western front. [Illustration: SCENE OF THE BLOODY BATTLES OF THE SOMME The tide of war swept over this terrain with terrific violence. Peronne was taken by the British in their great offensive of 1916-17; in the last desperate effort of the Germans in 1918 they plunged through Peronne, advancing 35 miles, only to be hurled back with awful losses by Marshal Foch.] The fighting-lines consisted generally of one, two, or three lines of shelter-trenches lying parallel, measuring twenty or twenty-five inches in width, and varying in length according to the number they hold; the trenches were joined together by zigzag approaches and by a line of reinforced trenches (armed with machine guns), which were almost completely proof against rifle, machine gun, or gun fire. The ordinary German trenches were almost invisible from 350 yards away, a distance which permitted a very deadly fire. It is easy to realize that if the enemy occupied three successive lines and a line of reinforced intrenchments, the attacking line was likely, at the lowest estimate, to be decimated during an advance of 350 yards--by rifle fire at a range of 350 yards’ distance, and by the extremely quick fire of the machine guns, each of which delivered from 300 to 600 bullets a minute with absolute precision. In the field-trench, a soldier enjoyed far greater security than he would if merely prone behind his knapsack in an excavation barely fifteen inches deep. He had merely to stoop down a little to disappear below the level of the ground and be immune from infantry fire; moreover, his machine guns fired without endangering him. In addition, this stooping position brought the man’s knapsack on a level with his helmet, thus forming some protection against shrapnel and shell-splinters. At the back of the German trenches shelters were dug for non-commissioned officers and for the commander of the unit.