I once saw a little dog snap at a big boy. The owner of the little dog apologized to the big boy for what his dog had done. But the big boy did not accept the apology, and he started in to thrash the little boy for what his dog had done. Presently a crowd gathered round, the friends of each boy took sides, and there was a general free-for-all “scrap.” So it was in this case. One of Austria’s big friends, Germany, took sides against Serbia, and Russia took the side of Serbia. Ever since the time of the Franco-Prussian War and Bismarck and William, Germany had been in training for a fight, and so had her neighbors. Nearly all the countries of Europe had for years been getting together into two groups, made up of the friends and the enemies of Germany; and the two were ready to jump at each other as soon as Austria, or Germany, or anybody else, struck at any one. But Germany didn’t strike at Serbia; Austria didn’t really need her help against Serbia. Germany was sure that France, who was her enemy and Russia’s friend, would take sides against her; and so she rushed at France to destroy her before Russia could hit hard from the other side. Now, to get at France Germany had to get through the little country of Belgium. She and France had agreed that neither would march armies through Belgium, but when the war began her armies marched in anyway and pushed aside the Belgians, who tried to stop them. And so her armies rushed on toward the capital of France, Paris. She got as far as a little stream called the Marne, only twenty miles from Paris. But here the French under General Foch stopped her army. This battle of the Marne is probably the most famous of all the battles you have heard about in history, for though the war was not ended for four years after this battle, if the Germans had won at the Marne, the war would have been over, with Germany victor, and the rest of the world would have had to do what Germany said. Germany was the first to use poison gas, trying to smother her enemy; she fought with submarines from under the sea; she attacked passenger ships that could not fight back. The English navy was the strongest, and it was only with submarines that Germany could fight at sea. This war was the first one in history in which battles were fought not only on land but up in the air and down under the water. England took sides with France and Russia--and these were called Allies--to fight against Germany and Austria, and at first the war was between these countries only. Before the war ended, however, almost all the countries of the world had taken sides against Germany, for they knew that if she won she would be able to tell the rest of the world what to do. Then all of a sudden Russia had a revolution. The Russian people killed their ruler, the czar, and his family, and refused to fight any longer. Things began to look pretty bad for the Allies.