Line Divisions:
On the right, the 30th American Division, to attack with the 60th Brigade, and to employ the 59th Brigade to form a southern defensive flank in the event of the failure of the Ninth Corps to cross the Canal.
On the left, the 27th American Division, to attack with the 54th Brigade, and to employ the 53rd Brigade to form a northern defensive flank, until such time as the Thirteenth Corps was ready to pass through in a north-easterly direction.
"Exploitation" Divisions:
On the right, the 5th Australian Division, with the 8th and 15th Brigades in the first line and the 14th Brigade following in support.
On the left, the Third Australian Division, with the 10th and 11th Brigades in the first line and the 9th Brigade following in support.
The total frontage was equally divided between the two pairs of Divisions, being about 3,500 yards to each. The battle was to be divided into two phases, the first to be executed by the Americans, under a timed barrage, the second, under open warfare conditions, by the Australians. It was intended that the Americans should penetrate to the "green line," an average distance of 3,500 yards, which took in the villages of Bellicourt, Nauroy, Bony and Gouy.
The Australians were to exploit eastward, but were limited to a further advance of 4,000 yards, overrunning Joncourt, Estrées and Beaurevoir. Should they reach that objective on the first day, they would have passed the last-known wired line, and the country beyond would be suitable for Cavalry. Accordingly, I allotted to the 5th Cavalry Brigade, which had been placed under my orders, the rôle of passing through the Australian Divisions, and carrying the exploitation still further east, in the direction of Montbrehain and Brancourt.
As it turned out, the whole of the objectives named were in our possession only on the forenoon of October 5th, instead of, as planned, by September 30th. The actual battle developed on totally different lines from those which I had planned, for reasons which I shall relate in due course. Little object would therefore be served in an explanation of the considerable mass of detailed arrangements which the original plan involved; these would also, by reason of their technical character, be more suitable for a text-book on tactics.
Suffice it to say that elaborate arrangements were made—and also partly utilized—for the rapid construction of four main roads from west to east, through the full width of the Hindenburg system. This work was to follow on the heels of the advance. The rôles assigned to the Tanks, the Barrage Artillery, the Mobile Artillery, the Heavy Artillery and the Armoured Cars were similar in character, although differing in detail from those carried out by them on August 8th.
On no previous occasion had the labour of preparation and the stress upon all Commanders and Staffs been so heavy, but all responded nobly. There were none who did not count the hours till zero hour, which was fixed for 5.50 a.m. on September 29th.
In appraising the long sustained fighting on the front of the Fourth Army which began on that day, and lasted a full week, regard must be had to contemporary events. The American First Army attack on St. Mihiel on September 11th had wrought fresh dislocation to the enemy's resources, and had created another sore spot on his long front. On September 26th the Americans and French again successfully attacked between Verdun and Rheims. On September 27th, the First and Third British Armies opened a great attack on a front of thirteen miles before Cambrai and the magnificent Canadian Corps captured Bourlon Wood and advanced to within a mile of Cambrai city. On September 28th, the Second British Army and the Belgians attacked between Ypres and the sea. All British Armies, except the Fifth, had, therefore, by that time developed active battle fronts. On September 29th the first French Army would co-operate with us, and on that day the battle front was to cover a total length of twenty-five miles.