Russians had at the outset only three divisions, and Mackensen's
earlier battles had shown that they were probably ill equipped
with munitions. Nevertheless, owing to the strength of the
positions, the battle was planned purely as a " trench warfare "
offensive, with technical equipment on the full scale regarded in
1915 as adequate.
Przasnysz (July 13-14). On July 13, after a bombardment of 3i to 6 hours, according to the circumstances of each sector, the infantry attacks of the XI., XIII. and XVII. German Corps were launched on either side of Przasnysz, on a total active frontage of about 20 miles. The defences in front of Przasnysz itself were threatened, but not attacked in earnest, by the 36th Div., the intention being to break through on both sides of the strongly fortified point and reduce it by envelopment. Everywhere the first line of the defence was carried. On the right of the XVII. Corps front the ist Guard Res. Div., and on the right of the XI. the 38th Div., attacking the faces of a small salient, cleared the way for the central division, the 86th repeating the same tactics at the second line. East of the Murawka the centre of the XIII. Corps (3rd Div.), after carrying the first line, was, unlike the XI. and XVII. Corps, met by a series of fierce though small counter-attacks, which hampered progress all along the line.
In the afternoon the German effort received a fresh impulse. On the XVII. Corps front the hitherto reserved 35th Div. was put in on the left of the ist Guard Res. Div., and this increment not only enabled the XI. and XVII. Corps to break through the right and the left of the Russian third line between Lysakowo and Choinowko but also to prepare to invest Przasnysz on the S.W. side. In the night of July 13-14 the Russians evacuated the few trench-elements that they still held and retired on the Przasnysz- Ciechanow switch-line. To the E. of the Murawka, the whole XIII. Corps front took up the offensive initiated by the 3rd Div., but progress remained slow, and at night only the first line and the western half of the second were in the hands of the Germans.
Nevertheless, the Russian strength did not yet permit of the large-scale counter-attack which alone could give them back the lost positions; and, rather than prolong, E. of Przasnysz, a third- line resistance which would be taken in flank and rear as soon as the victorious XVII. Corps should force the Przasnysz-Ciechanow switch-line, they decided to go back to the Bogate position forth- with. Thus the progress of the German XI., XVII. and XIII. Corps met with only rearguard resistance on July 14. Neither Przasnysz nor the switch-line was defended, while, to the W. of the battle-field, the German XVII. Res. Corps was able to advance, with no more than skirmishing, up to the outer defences of Ciechanow. The day's advance brought the infantry, but not the heavy artillery, of the attack group close up to the Bogate position, the eastern half of which the XIII. Corps in vain tried to carry with a rush at nightfall.
Bogate (July 15-77). In two days the Germans had advanced over nearly half of the 24 m. of ground which separated them from the Narew line, and as yet the Russians had shown no important reserves indeed, as late as July 12 troops were being withdrawn for the Mackensen front. The problem before the Germans was therefore to reach the Narew and master its crossings, if possible, before the enemy's reserves arrived and at the least to absorb these reserves in the defence of the river line. Speed was im- perative, and the Bogate position had to be attacked with a minimum of preparation.
The Russian position was carefully laid out. On the right it folio wed the obstacle formed by the Orzyc from above Krasnosielc to Podos, whence it followed the edge of a wood to Bogate on the Wengierka. From Bogate a N.-S. switch-line, and from Podos a second switch, ran to Karniewo, whence along a convenient stream the barrier continued to the Pultusk works. The W. half of the position three to four parallel lines close to one another was strong about Bogate and in the neighbourhood of Opino- gora and Ciechanow. In the Opinogora sector, a night attack on July 14-15 gave the German 38th Div. possession of some ad- vanced works and also a foothold in the first line itself near Zalozce Potory, but the advantage could not be exploited, and during the morning of July 15, while the artillery of the attack
was still ranging, Gallwitz fixed upon the centre of the E. half on both sides of Zielona as the break-through front. Here there were put in, besides the 36th, ist Guard Res. and 86th Divs., the newly arrived soth Res. Div., while on the right of the 86th Div. Pfeil's Bde. the only army reserve remaining was to follow en echelon. The break-through force was to penetrate well to the S., then swing outward on both flanks, so as to force the evacua- tion of Ciechanow on the one side and to attack the Bogate- Karniewo switch-line on the other. The attack of the XIII. Corps and of Falk was to be frontal; and from the strength of the Russian position and the relative weakness of the attacking forces (three and one-half divisions as compared with five and one-half W. of Bogate) no more than local gains were expected till a break-through further W. succeeded.
It was not until after midday on July 1 5 that the attack could be launched after a brief artillery bombardment. But it was successful on the lines intended. The three and one-half divisions on the assault front broke through all the defences, and penetrated so far S. (the s8th and 35th Divs. conforming on the flanks) that the Russians evacuated Ciechanow during the night of July 15-16. Further W., the XVII. Res. Corps and Dickhuth's Corps pro- gressed considerably toward the N. front of Novogeorgievsk, against no great opposition. But the Bogate-Podos-Orzyc river front of the defence held firm, as also did that part of the western position adjacent to Bogate.
On July 16, while the W. half of the break-through force sub- stantially, the XI. Corps pushed on southward, driving the Russian rearguards before them to the line Sonsk-Golymin Stary, and the XVII. Res. Corps and Dickhuth's Corps advanced along and W. of the Ciechanow-Novogeorgievsk railway, the XVII. Corps, now comprising the soth Res., the ist Guard Res., 35th and 3&th Divs., wheeled in against the Bogate-Karniewo switch- line, while the XIII. Corps and Falk assaulted the Bogate-Povos- Orzyc front in earnest. Both front and flank positions were stubbornly held. Local gains by the attack were nullified by local counter-attacks, and these were followed by new assaults. The soth Res. Div. had not succeeded by nightfall in coming within several kilometres of Karniewo the point at which the whole of the Russian position could be turned on their left; and on the other flank Krasnosielc, which equally afforded a gateway to the rear of the defensive system, was too strong to be reduced by direct attack. But between Bogate and Podos the Russian front line was forced along its whole length by the German 26th and part of the 3rd Divs., and the village of Podos, at the re- entrant angle of the position on the Orzyc, after changing hands more than once, was finally secured by the Germans about ii P.M. Further N. the attackers had reached, but not passed, the Orzyc. But on the switch-line Bogate-Karniewo the 36th Div. broke hi at Krasne, 2i m. S. of Bogate; and N.E. of Krasnosielc the I. Corps, hitherto passive, was now actively con- forming to the advance of the XIII. and Falk, and at the same time condensing its forces on its right. The general idea of the situation formed at Hindenburg's and Gallwitz's headquarters was that the last Russian counter-attacks were meant only to gain time for another evacuation under cover of night this time to the Narew and the bridgeheads. Accordingly, the Ger- man orders for July 17 not only directed the XI. (and part of the XVII. Res.) southward into positions for the attack of Pultusk, but deflected the 5oth Res. Div. there as well.
The Advance to the Narew (July 77-27). The impression of the situation formed by the German headquarters on the evening of July 1 6 was only partially correct. On the morning of July 17 the whole Krasnosielc-Bogate position and the northern position of the Bogate-Karniewo switch-line were found to be evacuated, or held only by light rearguards. But the German follow-up encountered more resistance than the similar operation on July 15. The Russians had in fact received the first of the expected reinforcements (about three divisions) and stood to fight, not indeed a battle, but a connected and determined rearguard action, on a line which, had it been completed, would have formed a third line of defence, similar to the Przasnysz and Bogate posi- tions. This line had its origin at the point where the Krasnosielc-
