According to reliable information, the scanty forces detailed for the defence of Constantinople had been strengthened by four Caucasus divisions,[49] already arrived or _en route_, and by some others from Anatolia, while Germany was sending German troops by way of the Black Sea. But the Turkish units were greatly reduced in strength by battle losses, sickness, and above all by desertions, and it was estimated that their total number of rifles was not more than 12,000 to 15,000. Towards the end of October it was known that the German troops were already leaving Thrace for Roumania, perhaps on their way to the Western front. The plan of operations of the new Allied expeditionary force was the following: The river Maritza was to be crossed by a surprise movement, and three bridge-heads were to be built on its banks, whence three columns would advance on Adrianople, Kuleli Burgas and Ipsala respectively. Immediately afterwards the bulk of General Milne’s forces would cut the Turkish Army in two, separating those in the Gallipoli Peninsula from those in Thrace, and occupying the Lule Burgas-Muradli-Rosdosto line, while the Allied fleets would bombard the enemy batteries in the Gulf of Enos. Finally, the Isthmus of Bulaïr would be attacked, with the object of seizing the whole of the European shore of the Dardanelles. Then the artillery fire would be concentrated on the batteries on the Asiatic shore. Once the Dardanelles were conquered the fleets could penetrate into the Sea of Marmara, whence it would be easy to force Constantinople to capitulate.