1917, ARRAS.—­The Somme fighting ends.  Again our armies are built up, until the 760,000 point is reached.  FRONT, increased to nearly 120 miles by a relief of French troops, falls again to 105, owing to the German retirement about ARRAS.  Heavy guns have increased from just over 300 to 1,500.  Again our armies are ready, and the Battle of ARRAS opens the ALLIED SPRING OFFENSIVE.  It is immediately effective, for casualties never reach the same height as in the Somme, and prisoners are much more numerous.  The lines for the two battles show the difference vividly.  But mark the big curve downward of the STRENGTH line.  Casualties are now not so easily replaced.

MESSINES, YPRES, PASSCHENDAELE.—­Before STRENGTH is fully restored the Messines ridge is rent with mines (June 7th) and taken.  July is devoted to preparation:  STRENGTH reaches its zenith, guns still increase, and on July 31st the Battle of YPRES opens the great northern offensive.  Fighting is bitter, and more costly than at Arras; CASUALTIES are at first high in relation to prisoners, but the PRISONERS line, as in the Somme, but more consistently, tends upward.  The German is not “sticking” the terrible conditions and fierce fighting so well as the Britisher.

CAMBRAI.—­Then, in December, comes our surprise attack at Cambrai:  it is effective, for PRISONERS nearly approaches CASUALTIES.  LINE increases, owing to the salient formed by the British advance.  Then, the German counter-attack, with CASUALTIES high, PRISONERS few, and LINE decreasing.  The Germans have reduced the salient made by our attack.

ITALY’S PLIGHT.—­But meanwhile, the enemy has struck at Italy, and Italy, reeling under his blows, is clamant for aid.  Division after Division hurries off!  STRENGTH falls, never again to ascend.  The handicap is permanent.

1918.  With STRENGTH almost at its lowest since 1916, after a year of ceaseless fighting and heavy casualties, with five Divisions diverted to Italy, miles of FRONT have to be taken over from the French.  Line held reaches its maximum, 130 miles. Fighting strength has fallen by mid-March—­when Divisions have been reorganised from 12 to 9 battalions, owing to the dwindling of reinforcements—­to 580,000.

THE GERMAN THRUSTS.—­The Chart has shown when we might attack.  Now it gives the warning to expect attack.  Now, if ever, is Germany’s moment, and her first great blow falls on March 21st—­the thrust at Amiens.  CASUALTIES soar to a height never before approached.  The red line predominates—­STRENGTH falls and falls.  Divisions are summoned from Italy and Egypt.  The second German blow falls on the Lys.  CASUALTIES are again immense, though not so high as in the first attack.  STRENGTH falls again.  The Lys salient increases the line held, but by the end of May the Line is firm throughout.  Some few thousand Americans for a time reinforce the war-weary British Divisions; but the Portuguese cease