Round about Krasnik they came into touch with the Russians, who held a strong position, with marshes and streams on their flanks. The army of the Archduke Joseph, to the left of von Mackensen, was heavily assailed, and during four days of attack and counter-attack was driven back with the loss of 15,000 prisoners, a very large number of machine guns, and heavy casualties in dead and wounded. For a week the German advance was checked. It began again on 16th July, when von Mackensen, who had bridged the marshy streams, was able to get his big guns working. Once more he blasted his way through, and on the 18th was within ten miles of the railway.
Now let us see what was going on in the north. On 14th July von Buelow's army in Courland began to push forward, and at the same time another army attacked the Niemen front. The great thrust against the Warsaw salient was entrusted to von Gallwitz, who now advanced against the line of the Narev. He made good progress, and the Russians fell back, fighting stubbornly. They retired across the Narev on the 20th, and three days later von Gallwitz won several crossings of the river. By means of one of these crossings he pushed forward until by 25th July, though the river line had not yet been won on a broad front, he lay within twenty miles of the Warsaw-Petrograd railway. Meanwhile the German heavy guns were battering down the outworks of the river fortresses, and the army of the Niemen was within sixty miles of Vilna.
The Warsaw salient was now in great peril. Spears had been planted against its breast in three different directions. At the apex a spearhead was but fifteen miles away; another was only ten miles from the southern railway, and a third was but twenty miles from the northern railway. The fortified line of the Narev had been broken through, and the salient was doomed. Once more the Grand Duke had to make a decision upon which hung the fate of the Russian armies. Should he try by means of the great Polish triangle of fortresses—Novo Georgievsk, Ivangorod, Brest Litovski—to hold the salient, or should he sacrifice Poland and fall back to the east? The second course was by far the more difficult. To withdraw his armies along the three railways left to him, while the spearheads were closing in hour by hour, and any day two of the three roads of escape might be lost, was a most perilous task. His wornout troops would have to hold the sides of the salient for some weeks while the main body retired. If the sides were forced in, it was more than likely that his armies would be utterly overwhelmed. It seemed easier to hold on to the fortresses, and hope that in some way or other the enemy might be checked.
The Grand Duke refused to take any risks; he chose the more difficult task. He determined to withdraw his armies from Poland altogether, and fall back eastward and ever eastward, until his forces could be properly fed with munitions and were ready to make a stand. It was a great resolve, and few commanders would have dared to make it. Probably no other army could have made such a retirement without losing heart altogether, and hopelessly breaking down.
The last days of July saw strange scenes in Warsaw. The whole city was stripped of everything that might be useful to the enemy. The great factories were dismantled, and their plant sent eastward. Gold from the banks, books and papers from the Government offices, relics and sacred pictures from the churches, bells from the towers, copper from the roofs, wire from the telegraph poles—all were piled on great wagons which followed each other in a long procession across the Vistula bridges. Half a million of the city's inhabitants streamed eastwards in carts and in hackney carriages. Only the Poles and the poorest of the Jews remained.
About 24th July the forces in front of Warsaw began to fall back into the suburbs of the city. Meanwhile along the Narev a fierce holding battle was being fought to enable the troops in the northern part of the salient to get away. Five days later Mackensen cut the southern line between Lublin and Cholm, and the sides of the triangle were fast closing in. By this time all the stores and guns were safe, and the troops in the centre were moving through the city. Every day German aeroplanes dropped bombs in the streets, and soon, as the German shells burst among the houses, great fires began to flame up in the western suburbs. At three o'clock on the morning of Thursday, 5th August, three loud explosions shook the city. The Vistula bridges had been blown up.
Three hours later German cavalry galloped in, and that evening Prince Leopold of Bavaria with his suite rode through the streets on the way to the palace. On the eastern horizon he saw the red glow which Napoleon had seen—the flames rising from crops and villages which the Russians had fired as they fell back before the invader.
The Kaiser made no state entry into Warsaw. His exultation, however, appeared in the following telegram which he sent to his sister, the Queen of Greece: "My destructive sword has crushed the Russians. They will need six months to recover. In a short time I will announce new victories won by my brave soldiers, who have shown themselves invincible in battle against nearly the whole world. The war drama is now coming to a close."