The Tsarevitch, the eldest son of the Tsar, is the Grand Duke Alexis, who was born on August 12, 1904. He was therefore eleven years old when, on September 5, 1915, his father took command of the Russian armies. Both father and son are seen wearing the uniform of the Caucasian Cossacks.] With the passing of all immediate danger, confidence surged up in their breasts, and at this moment the Tsar placed himself at the head of his soldiers. "We shall," he said, "fulfil our sacred duty to defend our country to the last." The Grand Duke Nicholas, who had so long borne the heat and burden of the day, gladly yielded place to his sovereign. Twice before in the history of Russia had a Tsar come forward to lead his armies in the day of dire peril. What Peter[59] and Alexander I.[60] had done, Nicholas II. now did. It was a sign to the whole Russian people that the war was to be waged to a triumphant end. The Germans were prepared to make a separate peace with Russia; they believed her to be crushed and broken and war-weary. Now came the reply: the Tsar, the head and front of Russia both in Church and in State, followed the example of his forefathers in the hour of trial and took chief command. * * * * * Look carefully at the large map on page 311, and find Grodno, on the Niemen. At the end of August the Russians were holding a salient round this fortress. September was but three days old when Grodno fell, and the Russians had to retire in order to avoid being surrounded. They had two railways to help them in their retreat--the main line to Petrograd and a line connecting with the Riga-Vilna-Rovno Railway. At all costs the enemy must be held back from these railways until the guns, troops, and stores in and around Grodno could be got away. Rearguards behind Grodno and a screen of troops farther north, where the Germans had to cross a district of lakes and forests, fought gallantly, and by 12th September the salient was clear. The Germans claimed to have captured 4,000 prisoners; but even if they did so, the price was not too high to pay for the safety of the army corps that escaped. Now we must turn to Vilna, against which von Hindenburg had prepared a great thrust. On 2nd September a ten days' struggle began fifteen miles to the north-west of the city. By sheer weight of artillery the trenches of the Russians were carried, and a gas attack gave the Germans an important pass between a group of lakes which formed the main defence of the fortress on their left. Other forces were pushing up from the south, and retreat was again necessary. By the 13th it was clear that Vilna must fall. The Germans had cut the Petrograd railway only twenty miles from the city. [Illustration: The Coming of the Big Guns that mean Victory. (_By permission of The Illustrated London News._)