resume the advance). This prevented I Corps from taking Kraewel's detachment from the east flank, which would have helped II Corps, which had halted after encountering a mixed brigade at Montreuil-sur-Lions, and was now fighting uphill through woods. On the left Pulteney's engineers did not have enough pontoons to cross the Marne (70–90 metres wide), and by nightfall half of 4th Division's battalions crossed on a makeshift floating bridge. The cavalry ("Gough's Command" on the left flank, Allenby's 1st Cavalry Division on the right, each maintaining contact with the adjacent French forces) was in Hew Strachan's words "entirely out of the equation". Sewell Tyng notes that the BEF had "exercised no effective intervention" in the battle and "remained no more than a threat which was never translated into decisive action", although Herwig points out that the men were exhausted after the long retreat, that the French cavalry performed no better and yet the advance – into the gap between the German First and Second Armies – had a decisive effect on the German commanders. Sir John initially thought (14 September) that the enemy was only "making a determined stand" on the Aisne. He urged the importance of entrenching wherever possible (23 September) and stressed (25 September) that heavy artillery would be necessary going forward. 1914: Autumn battles Race to the Sea After lobbying by Churchill, who was keen to bring the Channel Ports under British control, and by Wilson, French lobbied Joffre (27 September) for the BEF, which was less heavily gunned and more mobile than a similarly-sized French Army, to disengage and try to move around the Allied left flank, part of the outflanking movements known as the Race to the Sea. Joffre agreed in principle, although he had private doubts about having no French troops between the BEF and the sea and later came to believe that this move had, by using up scarce rail capacity for ten days, prevented him from reinforcing Lille and had allowed the Germans to capture it. Throughout September and October 1914 French warned Kitchener that his forces were running dangerously short of shells, at one point being rationed to 20 rounds per gun per day. French was impressed by the first 9.2-inch howitzers, but very conscious of German artillery superiority, and wrote to Kitchener (24 September) "Krupp is our most formidable enemy at present". French took a keen interest in the development