For the great battle for Paris or the coast, the great German invasion of France, which was also an attack on British sea-power, has shifted its centre from Ypres; and, while the Crown Prince of Prussia is hammering at Verdun, as the eastern gate to Paris, the French and British Army Commanders in the north-west of France have resolved to try to advance (to push the Germans further back, that is to say), on, roughly, a north-easterly front, looking from Amiens through Albert to Bapaume. This, broadly, is the key to a situation, which we have been following in diminishing degrees from the big, strategic plans in high places to the disposition of units and individuals. We have watched the preparations for that advance: the movements of troops by rail and road; the eyes of the army in the air; the ears of the army underground; the elaborate collection of war-material; the construction of permanent ways, and so forth. We see now the relation in space of the campaign of 1916 to the campaign of 1915. The tidal wave has ebbed away from Ypres, and has surged more furiously against Verdun; we are to change our focus, accordingly, from the Yser Canal to the River Somme, and from the Channel ports to Paris; and in this sector, narrowing our survey, as the vast movement unfolds into details, we are most particularly concerned with the straight line, laid on a Roman road, which runs south-west from Bapaume to Albert. It is rather more westerly in direction, and about half the length of the road down to Bapaume from Douai. Travelling along its well-laid surface from north-east to south-west, we pass through Le Sars, Pozières and La Boisselle, the last a little to the left of the line. The nodal point, or meeting-place, or starting-place, is the town of Albert on the Ancre, ‘a small, straggling town built of red brick along a knot of cross-roads at a point where the swift chalk-river Ancre, hardly more than a brook, is bridged and so channelled that it can be used for power.’[56] Westward from Albert is Amiens; eastward we saw, Bapaume. Next, follow the chalk-stream of the Ancre, northward under Albert’s bridges, through its native banks and braes. For our range of vision is being contracted, and we are coming through Army Commanders’ plans to the men appointed to carry them out in their destined stations along the line. About two miles north of Albert on the west bank of the Ancre are the first trees of Aveluy Wood, where our assembly-trenches lay. Martinsart lies behind this Wood, Mesnil and Hamel are beyond it, Bouzincourt just below it to the rear. Opposite, on the east bank of the Ancre, about three miles to the north of Albert, lies the village of Authuille, north of which again is Thiepval Wood, looking backwards at Hamel and Mesnil on the safe, west side of the little river, and facing ‘the German line opposite the Authuille section,’ just as Colonel Rendall (and, doubtless, many others) had imagined the situation in that