This was the first great war fought with the new weapons which science had provided. The Russo-Japanese War had, to be sure, tried them out somewhat and the Boer War had shown some things, but in the main the result upon warfare of the new artillery and the new rifle was not fully appreciated even by the Germans. One of the discoveries was shrapnel. This was a shell, thrown from a short-range gun—and a gun firing no more than three miles was short-ranged—timed to burst in the air and scatter over a wide area a great number of bullets or jagged fragments of iron. Flesh and blood could not resist it.

One of the great German surprises was the high explosive shell loaded with one of the super-powders or super-dynamites. The explosion was so tremendous that one shell falling upon a regiment would annihilate it; landing upon a trench it would simply wipe it out. Houses crumbled like cardboard and the most elaborate steel forts in Europe were turned upside down. There was only one way to meet that kind of shell and that was to keep out of the way. Then there was the machine gun, sending forth a stream of bullets, covering a wide area as fast as a man could turn a crank. The bullets were deadly and the stream was continuous.

The new cannon projected these shells and bullets astonishing distances. Rifles hitting at more than a mile were common; shrapnel was effective at great distances; and high-explosive shells could be shot with accuracy from five to ten miles. Eventually the large guns threw projectiles twenty miles or more, and one German freak cannon hit Paris from a distance of over seventy miles.

The result was that fighting in the open simply came to an end. Men in the open would positively be killed. A body of troops advancing across a field miles away from the German lines could be wiped out by high-explosive shells, if they were seen from a German aëroplane or balloon. Once they came within eyesight of the German batteries shrapnel could annihilate them, and long before they could get near enough to take a German trench, the machine guns could kill them all. They could not escape the three. At the end of the battle of the Marne, both armies were digging furiously to get into the ground out of sight. Nothing but Mother Earth could protect them from the new artillery. There came to be, therefore, in France, and to some extent in eastern Europe, nothing but a trench line from the mountains to the sea, in which both armies burrowed like moles in a desperate anxiety to get as far out of sight as quickly as possible.

It may be interesting to give a typical description of an approach upon the battle line from the open country at the rear. The first thing we come to is the army of supply which supports and keeps alive the army in the trenches. It is a city of huts and horse tents something like a mammoth circus. Passing through long stretches of it we come to the supply lines. Here we find the roads filled with motors, carrying all sorts of things, and small railroads, with little dummy trains puffing back and forth on tracks running out here and there like veins in the landscape.

Far away on the horizon, miles away, is a ridge with a row of charred trees, standing out gloomily etched against the sky. That is the battle line. We do not hear anything, but we see some fleecy balls of smoke. Those are the exploding shells. Suddenly from above comes a roar of noise and we see an aëroplane, or perhaps half a dozen of them, starting out for a trip across the lines or coming back from one. Up in the air out in front of us are floating around a number of fat sausages. They are observation balloons, in each one of which is a man with a glass trying to see where the German batteries are.

On we go an interminable distance, several miles perhaps, and we come presently to a plain which was once a wood. A battle was fought here some time ago. The trees have all been mowed down as if by some giant scythe or tremendous mowing machine; here and there a solitary tree trunk, which somehow was missed, sticks out of the ground: Presently we come to a sort of slit in the ground and begin walking downhill. Now the surface of the ground is up to our knees, presently it is up to our waist, and pretty soon over our heads.

We do not march straight forward, because the trench is not straight. It curves and zigzags and goes round sharp corners until we are dizzy and have lost all sense of the way in which we are going. That is so that a machine gun of the enemy would not be able to fire the whole length of the trench, in case they should happen to get in front of it. It also protects the people walking along the trench from the tons of chance bullets which the Germans and Allies were both continually shooting at each other in the hope that one of them might kill a man. Nothing but large masses of Mother Earth stops bullets.

We come presently to a line of trenches that runs at right angles with the one we have come through. These are the support trenches and there are sometimes several lines of them. We proceed from one of these lines to another, all of them more or less parallel, by means of communication trenches which zigzag back and forth from one to the other. No one sticks his head above ground if he can help it. He would be likely to lose it.

The front trenches are like the others, except that they are worse. Every once in a while a German shell blows out a section of them. In front of these a mound of earth has been thrown up or sand bags have been piled to make a sort of low parapet. Through cracks in this a soldier looks out to see if the enemy is coming, or he uses a periscope, exactly the same as the submarine uses. It is really an arrangement of mirrors, and is intended to allow one to look around a corner or over a wall. Looking through the periscope we see outside in front, a few yards away, a series of barbed wire fences. They are Allied entanglements to stop or delay a German charge. Some further distance off, in some places a long distance, in others only a hundred or two hundred yards, are other fences. Those are the German wire fences. The ground in between looks as if it had been stirred with some giant egg beater and churned up into mud. It is pitted all over with enormous holes where the high explosive shells have struck.

There in these trenches in the ground, looking through periscopes, sit the Allied soldiers, watching another series of holes where the Germans are sitting. A certain amount of shooting is going on all the time and the humming of rifle bullets and the scream of shells is constant. Then will come a great scream, announcing the arrival of a big shell. All the noise in the world seems concentrated on that spot and the earth shoots up like corn popping in a pan.

At night the trench line looks like a continual display of fire-works. Darkness is the most useful thing in modern warfare because at night it is more difficult to see people. Then the soldiers come out and repair the barbed wire, mend trenches, and go back and forth to the rear without much danger. In the day-time even an automobile moving along a road so far away that the cannonade sounds like little more than a rumble is in danger of being hit. To prevent the enemy from rushing, the trenches both sides keep sending up lights called star shells. Little balloons also are sent up carrying lights which float around and burn a long time. Some of these are so very brilliant that they light up whole sections of the line almost like daylight. When the artillery fires at night, the flashes make a magnificent spectacle. In the day-time trench warfare is not very picturesque; at night it is magnificent.

This was all the result of the necessity of getting out of sight and it at once transformed warfare. The old battle had been one of movement. One formation of troops marched against another. One general tried to get his army on the flank or in the rear of the other general's, and it was always possible because there was plenty of open ground to move over. But the number of troops engaged in the present war was so enormous that they spread out over miles of ground. The German invasion advancing into France was over one hundred miles broad, and when that number of men began to dig into the ground to get hidden, it took an extraordinary number of miles of trenches to hide them. The battle line started in half as wide as France and presently was continued all the way to the sea.

Movement in the old sense became impossible: there were only two ways to move. One was forward and the other was back, and both sides only wished to go forward. This meant that the only possible attack was a direct frontal attack upon prepared positions. The only thing either side could do was to charge straight at the other and attack the enemy exactly where he was expecting to be hit, exactly where he had concentrated his guns, was ready to do the most damage, and receive the least injury.

The Germans at first believed (as the Allies also did) that, if only enough men were sent out to rush the enemy trenches, they could capture them. It would cost a good many lives but it could be done. But presently the idea had to be given up. There were too many ways of checking the charge long enough to kill every man who started. The big guns could begin with the charge when it first left cover a long distance away, the shrapnel could continue the work as they came nearer, and then the machine guns could open up. The barbed wire would effectively prevent their getting at the front trenches until they had been riddled with bullets. Hand grenades, or small bombs thrown by hand, could be tossed out into the advancing troops by the defenders and would kill numbers of men. Then mines could be laid out in front of the trenches and exploded by electricity when a whole regiment of the foe was standing on them. Flesh and blood could not overcome such resistance. Some other method of attack had to be found.

Spreading the men out on the field instead of allowing them to advance shoulder to shoulder was promptly tried. The difficulty here was that more men got through out of those who started, but that not so many could start, and the weight of the charge was likely to be lost. It is just the same problem as that of a football eleven which spreads out five feet apart and then runs at its opponents. The men cannot go so far as when massed together.

Then the accuracy of the artillery fire became so great as the first months passed that a sort of attack which was very successful at the beginning of the war was destroyed before it had gone a hundred yards after the war was a year old. The shrapnel fire became absolutely accurate, the machine gun fire sure death to anything within range, and even the big guns, miles away, soon were able to hit a moving object with great frequency. It was difficult to get out of the trenches without being annihilated; it was almost as perilous to stay in them. Both sides experienced the same trouble.

It was clear that the decisive factor in the new warfare was the artillery and that the large artillery played the most important part. It was absolutely imperative to defend the Allied trenches from the German artillery by keeping it back out of range. The big Allied guns must be sufficiently prompt and accurate to wipe out all small German guns which were likely to fire upon the infantry at short range. They would never be able entirely to clear them out, but unless they demolished a considerable number, the Allied trenches could not be held. Of course, small guns of all sorts and kinds could be kept, and soon were, within the battle area by both sides, provided they did not reveal themselves to the foe by firing. This came gradually to be the rule: guns within range of the enemy's big artillery must be thoroughly concealed or must keep quiet until an infantry attack should take place. Then the enemy's large guns must stop firing to allow his own infantry to move into that area.

On the offensive, the artillery was absolutely the essential factor. It must first accurately blow out of the ground the barbed wire entanglements of the enemy. Otherwise the Allied troops would be held up and killed. It must also destroy the bulk of the machine guns and small artillery within the entire area the Allied troops were to attack. If it did not succeed, they were absolutely certain to be killed. If the artillery did its work properly, the infantry could then move forward and occupy as much territory as the artillery could "prepare," as the phrase went. It was demonstrated early in 1915 that it was perfectly easy to destroy any section of the enemy front line by artillery fire and then occupy it at some cost of life so long as the infantry kept within the protection of their own artillery.

It was merely a question of the amount of ammunition which had to be fired in order to destroy the enemy defenses. To be sure, that amount turned out to be extraordinarily large, but the real cost of taking the other lines was ammunition, not lives. But if enough ammunition was not spent, the price in lives was sickening. Even after proper artillery "preparation" it was not at first possible for the infantry to go forward more than a few hundred yards. Every step they advanced beyond a certain short range, they were leaving their own guns behind and running into the range of the German artillery which their own guns had not yet been able to destroy.

It was soon clear that the artillery could not move forward as fast as the infantry did, but it was also clear that the infantry would be exterminated the moment they went faster than the artillery. It was easy to go a short distance, but not particularly worth while. Days and months were necessary by this method to move into the enemy's defense for a few miles, and the trenches were of such a simple nature that he could dig new ones almost as fast as the Allies could take the old ones. A zone of trenches several miles wide, the Germans calculated, would be a perfect defense, if prepared in advance and protected by artillery. Human beings could not enter it and live.

The Germans now began to systematize the new warfare. If the game was to destroy the trenches, the machine guns, and small artillery within a certain area. so that the infantry could then come over and occupy it, the answer was simple. Even the largest shells did not penetrate into the earth more than a few yards. If, therefore, fortifications were built of concrete and timber thirty or forty feet underground, the Allies might pound them with as large shells as they pleased. They could not destroy them. Protection was merely a question of depth. When the Allied artillery began to fire, all the Germans needed to do was to retire to the underground forts and wait, playing phonographs, eating, or sleeping until the enemy should get through. The Allied guns would have to stop firing to allow their own infantry to advance, and, when the silence began, the Germans would know that the Allied infantry was coming. They could then climb upstairs and annihilate them with machine guns.

Of course, it was true that the Allies could and did play this same game. By it, they could prevent the Germans from winning the war, but by it, undoubtedly, the Germans could also prevent them from winning. Modern warfare had produced a deadlock. Neither side seemed to be able in 1915 to make any progress nor did either of them make in France any real progress for three years.