Already several planes were in the air, bent on various missions. Here one had ventured over the enemy lines, and was circling high up, daring a Boche pilot to ascend and give battle. Another was striving to get above several sausage observation balloons that were rising back of the German lines, hoping to be able to drop a bomb with telling effect on one of the group.

These things always bring about fierce fighting in the air, and hardly a day passes without a number of machines on either side being shot down, the fate of their human occupants sometimes never wholly known.

Tom had not forgotten one thing. In his pocket he was carrying a letter from his American instructor, Lieutenant Carson, to his younger brother, who was flying for France in some capacity. He learned however that Philip Carson was not just then connected with the Lafayette Escadrille, though he was known to most of those who formed that corps.

Some time later on perhaps Tom might chance to run across Carson, for somehow Americans seemed to have a way of finding one another over there in France. Perhaps they were drawn together by a desire to chat in their own tongue; for but few of them could be said to be really proficient in the French language.

A score of things interested the boys from the start. As they as yet had no planes of their own they were privileged to roam about, and make numerous delightful discoveries. Later on they would be sent up with one of the other pilots, perhaps to take photographs of the enemy country back of the lines.

For this purpose a heavier machine than the Nieuport was always used, which went by the name of Caudron. This plane, being a two-seater, was frequently utilized to carry a spy far back of the German lines, where he could be dropped, to be called for at a specified time later on, after he had collected his information.

When one of these heavy planes went out on a reconnaissance it was equipped with a complete though small wireless outfit. Besides this Tom found—something that for some reason he had not before known—that a number of homing pigeons would be taken along, these to be released one by one as the pilot picked up news that he considered worth sending back in haste to the camp. Thus it might reach General Headquarters, and possibly prove of vast value in warding off a threatened attack.

Jack was most interested in the bombarding machines. These were of a peculiar build, and so fitted that they could take up a certain number of highly destructive bombs, carried underneath, where at the proper time each in turn could be detached, to fall through space and do its appointed work.

He asked many questions of the grizzled sergeant whose acquaintance he made, and learned the method by which the raids were conducted on enemy munition dumps and concentration camps far back of the fighting front; or it might be, how a plan was carried out by means of which a deadly blow was struck at some fortified city hundreds of miles back in the Rhine country.

Tom was interested in the fighting planes. He noted the grimlooking little rapid-fire guns which they mounted, and touched the various parts with an almost reverent air. In truth the dream of his life was now close to being realized, and Tom was happy.