Herzegovina, and Old Servia, have long been a thorn in Austria's side. The Austrian emperor, himself, in an address from the throne, stated that 'the flame of the hatred of Servia for myself and my house has ever blazed higher,' and he declared—not without reason—that 'a criminal propaganda has extended over the frontier.' It must be remembered, however, that this propaganda was Austria's fault, for she tore up the Treaty of Berlin in 1908 just as Germany tore up her treaty with Belgium the day before yesterday.

"Just a word, Monroe, about the 'balance of power.' In order for Europe to live at peace, no one nation or group of nations must be allowed to get too strong. Since Germany and Austria are allies, other nations must form defensive alliances, and one of the strongest of these was between France and Russia."

"Why those two?" queried Horace. "They're not neighbors."

"No," the master replied, "but they are both neighbors of the Central Powers. France seeks revenge from Germany for the Franco-Prussian War of 1871, when Alsace-Lorraine was taken from her. Russia could never cope single-handed with the military forces of Germany and Austria. If, however, the Germanic powers attacked either France or Russia, by this alliance they would be confronted by an enemy on the opposite frontier."

"So when Russia had to back up Servia," said Horace slowly, "France had to back up Russia. Is that it?"

"Exactly. Now, see where England stands. By a naval agreement with France, the British possessions in the Mediterranean are watched over by a French fleet. The English Channel, which commands the north shore of France, is patrolled by a British fleet. On Saturday last, three days ago, England assured France that, in the event of trouble with Germany, she would protect French interests in the English Channel and the North Sea. This bottles up the German fleet. That, you see, my boy, is where the nations stand. Now let us come to the actual beginning of the war."

Horace redoubled his attention, leaning forward with one elbow on the table.

"On June 28, five weeks ago," the master continued, "the heir to the throne of Austria, the Grand-Duke Francis Ferdinand, together with his wife, were shot and killed by a Servian student. The crime occurred in the streets of Serajevo, capital of the province of Bosnia, which Austria had wrongfully annexed six years before. Austria claimed that the assassination was part of a plot known to the Servian government, but this charge was denied and has never been proved.

"For three weeks there were no outward signs of a storm. Probably the time was spent by Austria and Germany in arranging the details of war. On July 23, Austria sent an outrageous and peremptory ultimatum to Servia. That little country, realizing that the assassination had placed her in a false position, acceded to all Austria's demands save one, which she could not yield without giving up her own sovereign rights."

"Which, I suppose," interjected Horace, "she wouldn't do. No country would."

"The ultimatum," continued the master, "only gave Servia two days' time to reply. This haste was for the purpose of forcing the issue before the other Powers could take action. Russia, the next day, asked Austria to give Servia more time. Austria, in consultation with Germany, told Russia to keep 'hands off.' It was clear, then, that Austria intended to use the assassination as a pretext to gobble up Servia in the same way that she had gobbled up Bosnia and Herzegovina six years before. Russia commenced to mobilize her army to help Servia, if help were needed. The Austrian army was already mobilized on the Servian frontier."

"Just what is mobilization, sir?" asked the boy; "I've heard the word used so much during the last few days."

"Mobilization," answered the master, "means getting ready to move. It means the organizing of an army, bringing troops from distant garrisons, artillery from concentration points, arranging food depots from which provision trains can be run regularly, munition depots to feed the guns, preparation and equipment of hospitals in the field and at the bases, wounded transportation and ambulance systems, stables, forage depots and veterinary stations for the cavalry and artillery horses, repair shops for military machinery, supply depots for uniforms and equipment, and a thousand other things besides. Each of these must interlock and have its place. Each one must move along a route, mapped out in advance and by a time-table as rigid as that of a railroad. A modern army on the march is a segment of civilization on the move and almost every department of human industry is represented. The mobilization and handling of an army is the most staggering problem of organization known to the human race."

"One never thinks of all that," said Horace, thoughtfully.

"To proceed with the events that led to war," the master continued, looking at his watch and speaking more quickly. "On July 25, Austria notified Servia that she was dissatisfied with the reply to the ultimatum. This was equal to a declaration of war. The next day, Russia, seeing Germany's hand behind the Austrian plot, warned the Kaiser that interference would not be tolerated. This declaration from Russia imbroiled her ally, France. Belgium, being required to keep an army of defense on her frontier, commenced to mobilize also.

"The very next day, July 27, the Austrians invaded Servia. At almost the same hour, shots were exchanged between German and Russian sentries on the frontier. On July 28, war began between Austria and Servia. Great Britain, at this time, was striving with might and main to keep the war from spreading and had urged both Germany and Russia to keep the peace.

"On July 31 Germany forced the European War by simultaneous action at two points. She sent an ultimatum to Russia, ordering her to cease mobilization within 12 hours. She sent an ultimatum to France demanding neutrality and asserting that she would require the keys of the French fortresses of Verdun and Toul as guarantee of that neutrality."[1]

"By what right?"

"None in the world! It was impossible for Russia to demobilize, with her neighbor and ally Servia already under the fire of Austrian guns; it was equally impossible for France to hand over the keys of her main defensive positions to her arch-enemy.

"On August 1, Germany declared war on Russia, and advanced her army to striking distance of the Belgian frontier. On August 2—that was the day before yesterday—German troops crossed the French frontier at three points and invaded Luxemburg, an independent state. That evening, Germany notified Belgium that she intended to violate her neutrality."

"Why is Belgium supposed to be neutral? Can't she go to war? Isn't she an independent country?"

"She is," was the reply, "but her war-making powers are withheld by the universal agreement of the Powers. Belgium is the key to Western Europe. Peace depends on Belgium's good faith. According to a treaty signed in 1839, we form 'an independent state of perpetual neutrality,' this treaty being signed by France, England, Prussia, Austria, and Russia. In 1870, during the Franco-Prussian War, Germany declared that this Belgian treaty could not be violated. In 1911, Germany repeated the assurance and again in 1913. All the while she had drawn maps for the invasion of Belgium and had built military railways to threaten our