My War Memories, 1914-1918 at our disposal in East Prussia. The forts in which an enemy corps or army staff had its quarters were often bombed. Splendid results had been reported; but when I was able to have the damage inspected it was impossible to verify it. In the interests of the troops I was glad of this, as they were able to use the forts as billets. It was only later that our bombs became effective, when the airmen took more interest in bombing work. As the advance progressed it became evident that Mackensen's and Prince Leopold's Army Groups were pushing north, and thus forcing the I2th and 8th Armies to the left. On August i8th Field-Marshal von Mackensen had arrived before Brest-Litovsk; Prince Leopold of Bavaria was approaching the Bialoviesa Forest, and the I2th Army Bialystok, the former seat of the excellent Prussian administration of New East Prussia at the end of the eighteenth and the beginning of the nineteenth centuries. The 8th Army pressed forward towards Grodno in the narrow space between Bialystok and the Narew, so as to capture Osowiec from the south. This fortress was invested on August 22nd. We had intended taking it from the east and north, yet we took it from the south. Such is war. In the latter days of August both armies continued the advance in a more north-easterly direction beyond the Bialystok-Osowiec line, the I2th Army marching north of Wolkowysk, and the 8th Army on Grodno. Both these armies, therefore, were gradually losing touch, tactically, with the two southern army groups, which, after the occupation of Brest-Litovsk on August 25th-26th marched on towards Pinsk and Baranovici. By degrees they came within the sphere of the operations which were in preparation further north. Early in September the 8th and i2th Armies reached the south-eastern outskirts of Grodno. In a fortnight's time or so they were to be at Lida, north of the Niemen. About eight weeks would then have elapsed since the offensive started. During this operation the I2th Army had had to make a long detour to the south. How much better wbuld it have been if, instead of this movement, an attack on the Lomza-Grodno line had been possible. That could not be done. But an opera- 158