In the front line every precaution against accidents was taken. The attacking divisions occupied their positions in line, but the old troops remained in the outpost line in case the enemy should secure identification; also patrols were ordered to avoid any possibility of capture.
On the 14th November the Corps ordered the 56th Division to hold the line with two brigades instead of three, so as to have a concentrated force ready to act in case of necessity. So on the night of the 18th the 167th Brigade extended its left and took over the frontage of the 168th Brigade, which concentrated in Fremicourt and Beugny, to the east of Bapaume.
On the night of the 19th the dummy Tanks were put in position about 300 yards from the front line. At 2 a.m. on the 20th gas drums were 176 projected into the German lines where the wire-cutting had taken place (Quéant), and at 6.20 a.m. the whole of the artillery on the Third Army front opened on the enemy lines with one stupendous crash.
In the 56th Division front line all was activity. The parties with the dummy figures moved them up and down in as lifelike a manner as they could, and other parties hurled smoke grenades so that the enemy might not see too clearly.
The “make-believe” attack was a great success. The Germans opened frantic and furious fire with machine-guns and artillery, and the dummy Tanks were shelled until mid-day!
By 9.15 a.m. the 36th Division (109th Brigade) had advanced along the west bank of the canal from the Spoil Heap to the Bapaume-Cambrai road, where the 169th Brigade joined up with it on the old German outpost line.
Meanwhile, great events had been taking place on the right. The III Corps, on which so much depended, advanced through the Hindenburg Line in grand style and, thanks to the rapid action of the 29th Division (General de Lisle), which was to wait until news arrived of the capture of the Hindenburg Support Line before advancing but attacked instead on observer reports, seized Marcoing and Masnières. The first bit of bad luck happened at Masnières, where the enemy had only partially destroyed the iron bridge over the Escault Canal. It might have been sufficiently strong for cavalry to cross over, or it might have been repaired to enable them to do so, but a Tank attempted to cross first and broke through it altogether. This unfortunate accident did not stop a squadron of Canadian cavalry, who, with the dash usually 177 associated with that arm, rode over a flimsy bridge across a lock on the Marcoing side of the town and attacked the enemy on Rumilly Ridge. It was probably troopers from this very gallant squadron who reached the outskirts of Cambrai.