Alone and unaided, Pilot Travers copes with the invisible foes who have struck down America's great engine of war. Excerpt The war game around the Canal was planned for more than practice, however. The eyes of the whole world were on that array of America's ocean might--the eyes of one foreign nation in particular. Washington knew of the policies of that nation, and wished to impress upon is the hopelessness of them. More than a game, this concentration of sea and air-borne fighting power was a gesture for the continued peace of the world--a gesture strong with the hint of steel. Chris Travers was vaguely aware, through the rumors of the mess-room, of the double meaning of the game he was playing his part in, but this morning he didn't give a single thought. He was too wrapped up in his job of spotting the van of the Black Fleet, radio-telephoning latitude and longitude to the bridge of the Blue Fleet flagship, and getting home to his dirigible without being declared destroyed by one of the war game umpires. Therefore, half an hour later, his heart thrilled as he glimpsed, wraith-like on the steely horizon, a wisp of smoke.