By the beginning of August, Sir Ian Hamilton had the following military forces under his command: VIIIth Army Corps (29th, 42nd, and 52nd Divisions); IXth Army Corps (10th, 11th, and 13th Divisions); Anzac Army Corps (Australian and New-Zealand-and-Australian Divisions); French Corps Expéditionnaire d’Orient (1st and 2nd Divisions); General Headquarter Troops (Royal Naval Division), together with the infantry of the 53rd and 54th Divisions then on their way out. Eleven divisions present and two more coming represented a nominal force of about 240,000 to 250,000. The actually available forces amounted to less than half those numbers (about 120,000 rifles), always short of howitzers, guns, shells, trench-mortars, and bombs. The Turkish forces on the Peninsula at the same time were estimated at about 61,000, with 39,000 in reserve.[148] The reinforcements by land and sea rendered a change of strategy possible. They were, in fact, supplied for this purpose. It had now become evident that the Achi Baba lines were too strong for direct assault. Its gradual slopes, free from dead ground, made the hill an ideal position for defence, and this natural advantage had been so increased by a complicated system of frontal and communication trenches, by barbed wire, machine-guns, scattered batteries, and a series of powerful redoubts, that an almost impregnable fortress by this time checked further advance. In fact, the army at Helles was like a besieged garrison, being continually threatened with assault from the front, and by the Asiatic guns on its right flank and rear. The sea remained open, but that outlet for communication, already exposed to the enemy’s submarines and heavy artillery, would soon be imperilled by autumnal storms. The Army Corps at Anzac was similarly besieged, except that the dead ground sheltered by precipitous cliffs reduced the danger to life in rear of the firing trenches. To break down the siege a sortie in force had become essential. The only alternative was to cling to the positions in the hope of a diversion from Russia or Bulgaria. But during July the great Russian retreat from Galicia and Poland continued almost uninterrupted, and on August 4, Warsaw fell. As to Bulgaria, the Russian disasters confirmed Tsar Ferdinand’s confidence in the ultimate victory of his German compatriots, and a resolute people’s ancestral detestation of the Serbs gave him the support of their passionate desire to recover the lands lost to them in the second Balkan War. [Sidenote: REJECTED SCHEMES FOR FRESH ADVANCE]