About 13th November Ruzsky's outposts along the Vistula were driven in, and his scouts reported that a very strong force of Germans was advancing along both banks of the river. The Russian general had far too few troops to meet the large numbers now flung against him, and, as I explained in the previous chapter, he could not expect reinforcements either from the south or from beyond the Vistula for a considerable time. He was, therefore, forced to retire, and by the 16th November the Germans were fifty miles to the east of their frontier, and half-way to Warsaw. No doubt during their advance they captured many prisoners and many guns, but owing to the straggling character of the Russian march, which was described on page 239, the losses of our ally were not so high as they would have been in the case of a Western army. The Turkomans,[168] mounted on fine horses, and wearing orange and scarlet sheepskin coats, flashed to and fro in the midst during many rearguard actions, and managed to delay the enemy's advance. One of these delaying fights took place on the night of the 15th-16th November, and was claimed by von Hindenburg as a great victory. He reported that he had captured 28,000 prisoners, and Berlin went mad with delight. The commander-in-chief was at once rewarded--he was made a field-marshal. Ruzsky's idea was to fall back in good order behind the river Bzura, which rises near Lodz, flows northwards for twenty or more miles, then runs eastwards for about forty miles, and finally flows north to join the Vistula, some ten miles below Lowicz.[169] During its eastward course the river flows through a great belt of marshes, which lie partly in the course of the river and partly to the west of it. The marshes are crossed by a few small paths totally unfitted for the passage of large bodies of men with heavy guns. All the bridges along the river had been broken down, but in its upper reaches the river could be forded. Look at this little map. You will find on the railway from Thorn to Lowicz the town of Kutno, and almost due south of it, beyond the Bzura, you will see Piatek. Between these two places the marshes are crossed by a great causeway, along which the heaviest traffic can make its way. From what I have told you of the Bzura, you will gather that an army lying behind the marshes of the river would be in a very strong position to meet a frontal attack. They could only be assailed in front along one road--the causeway already mentioned. They might, of course, be outflanked by a force crossing the river below Lowicz (A), or fording the stream to the south of the marshes (B). The Germans, as we shall see, made not only a frontal attack along the causeway, but also flanking attacks at A and B. [Illustration: Diagram showing the Russian Position behind the Marshes of the Bzura. Notice the causeway leading from Kutno to Piatek. Along this causeway the Germans made their frontal attack.]