Disposal of the Third Army--Attack upon the Third Division--Upon the Thirty-fourth Division--Upon the Fifty-ninth Division--Terrible losses--Loss of Henin Hill--Arrival of Thirty-first Division--Hard fighting of the Fortieth Division--The East Yorkshires at Ervillers--The 15th West Yorks at Moyenneville--Recapture of Ayette--Grand resistance of Third, Fifteenth, and Fourth Divisions before Arras--Final German check in the north. [Sidenote: Third Army. March 21.] Taking the account of this great action upon March 21 from the north, we shall begin with Sir Julian Byng's Third Army. The left of this force joined the Thirteenth Corps, which formed the flank of the First Army, to the north of Fampoux, while the extreme right touched the left of the Seventh Corps, the northern unit of the Fifth Army to the east of Metz-en-Couture opposite to Cambrai. The Seventeenth Corps consisted of the Fifteenth and Fourth Divisions with the Guards Division in reserve. They extended as far south as the Sensée River, and were not seriously engaged upon March 21, though exposed to heavy shelling. We may for the time leave them out of the narrative. It was immediately to the south of them, upon the Sixth Corps commanded by General Haldane, that the storm {14} burst in its full fury. Nothing can exaggerate the concentrated weight of the blow which fell upon this and the next portion of the line. The divisions from the north were the old fighting Third upon the Sensée section, the Thirty-fourth to the south of it, and the Fifty-ninth North Midland Territorials on the right. The Fortieth Division was in close support. These were the devoted units who upon that terrible day had to bear the heavy end of the load in the northern half of the line. Let us turn first to the arduous experiences of the Third Division. This veteran division, still commanded by General Deverell, had all three brigades in the line, the 76th upon the left, the 8th in the centre, and the 9th upon the right, the battalions in the advanced line being the 2nd Suffolks, 2nd Royal Scots, and 1st Northumberland Fusiliers. The front covered was 8000 yards from Croisilles to the Arras-Cambrai Road in the north, both inclusive. This front had been strengthened by every device which experience could suggest, and was organised, as already explained upon three lines, which may be called the front, support, and reserve lines. Its backing of artillery was formidable, its moral high, and it offered a solid barrier to any enemy, however numerous. [Sidenote: Sixth Corps. March 21.]