thousand feet and content with that height and flying level, he glanced about and saw that the machines which followed him were flattening out too and in position. He gazed at his mapboard where was displayed chart of the land below with notation of the battle line—such battle line as still existed—corrected up to the last hour by photographs and visual observations made by other pilots that morning. It was the strip of ravaged and restored land over which he was flying; clearly he could see the cross-streaked spots of the cities; on his right, Ham; on his left, Péronne and Roisel. Roads spider-webbed about them; tiny villages clustered. Immediately below he could see even, decent patches of planted fields, gardens, meadows; he could make out, too, more minute objects—the peasants' cottages and their trees, the tiny roofs of the new portable houses supplied by the Americans.
He could see the specks which were people upon the roads, gathered in groups moving together; where the specks formed into a long, ordered line, he knew that they were troops and moving toward the battle, probably. He himself was flying so fast that the direction of the slow movement upon the roads could not appear; but he could guess that the irregular series of specks were refugees in flight. Shells were smashing beside them—shrapnel, high explosive, and gas. He could recognize easily the puff of the shrapnel distinct from the burst of the high explosive shells. He could not distinguish the gas shells; but he knew that the Germans were using them, deluging with gas the zone behind the battle to a depth unknown before.
He gazed forward to the ground where the German
