General Leman realized, therefore, that, without a supporting field army, it would be impossible for him to hold the German hosts before Liege for more than a few days--a week at most. But he hoped within such time the French or British would march to his relief. Thus his chief concern was for the forts protecting the railway leading from Namur down the Meuse Valley into Liege--the line of a French or British advance. On the afternoon of August 4, 1914, German patrols appeared on the left bank of the Meuse, approaching from Vise. They were also observed by the sentries on Forts Barchon, Evegnee and Fleron. German infantry and artillery presently came into view with the unmistakable object of beginning the attack on those forts. The forts fired a few shots by way of a challenge. As evening fell the woods began to echo with the roar of artillery. Later, Forts Fleron, Chaudfontaine and Embourg were added to the German bombardment. The Germans used long range field pieces with powerful explosive shells. The fire proved to be remarkably accurate. As their shells exploded on the cupolas and platforms of the forts, the garrisons in their confined citadels began to experience that inferno of vibrations which subsequently deprived them of the incentive to eat or sleep. The Belgians replied vigorously, but owing to the broken nature of the country, and the forethought with which the Germans took advantage of every form of gun cover, apparently little execution was dealt upon the enemy. However, the Belgians claimed to have silenced two of the German pieces. In the darkness of this historic night of August 4, 1914, the flames of the fortress guns pierced the immediate night with vivid streaks. Their searchlights swept in broad streams the wooded slopes opposite. The cannonade resounded over Liege, as if with constant peals of thunder. In the city civilians sought the shelter of their cellars, but few of the German shells escaped their range upon the forts to disturb them. This exchange of artillery went on until near daybreak of August 5, 1914, when infantry fire from the woods to the right of Fort Embourg apprised the defenders that the Germans were advancing to the attack. The Germans came on in their customary massed formation. The prevalent opinion that in German tactics such action was employed to hearten the individual soldier, was denied by their General Staff. In their opinion an advantage was thus gained by the concentration of rifle fire. Belgian infantry withstood the assault, and counterattacked. When dawn broke, a general engagement was in progress. About eight o'clock the Germans were compelled to withdraw. [Illustration: Beginning of German Invasion of Belgium.]