Great work was done at this period by four of the Canadian motor-guns at the cross-roads, north-west of Rouvroy, where they not only inflicted heavy losses upon the enemy but delayed his advance while the exhausted troops were settling down into this new position. Every hour was of importance as giving reinforcements time to come up from the rear, and the general orders to the divisional generals were to hold on at all costs wherever defence was possible. A small body of corps cyclists under Lieutenant Quartermain co-operated splendidly with the motor-guns and did good service at this critical period of the retreat, during which there was very little artillery support behind the thin line of infantry. [Sidenote: March 27.] The German pressure on March 27 fell chiefly, as already shown, upon the Twenty-fourth Division and the other units on the extreme south of the Nineteenth Corps, which were forced back for some distance, and so threatened the stability of the line in the south. The 17th King's Liverpool, which was the flank battalion, held fast, however, and flung back their left to form a defensive line to the north. A small body of German cavalry performed a brilliant piece of audacious work in the darkness of the early morning of this date, pushing through the outposts of the Thirty-sixth Division in the south near Guerbigny, and capturing the Brigade Headquarters of the 109th Brigade, and also the chief staff officer of the division. The future was full of menace, for the Germans {173} were pressing on in great numbers. An observer near Bouchoir that evening (March 27) says: "I have never seen so many Germans in all my life--one huge dark mass about a mile away. With glasses one could see howitzers, machine-guns, trench-mortars, and field batteries, as well as infantry. It was a most wonderful sight. They seemed to be coming down the Roye Road, then moving off to the south, and some stopping in a mass."