Tam lived with the men--he had the rank of sergeant, but he was as much Tam to the private mechanic as he was to the officers. His pay was good and sufficient. He had shocked that section of the Corps Comforts Committee which devoted its energies to the collection and dispatch of literature, by requesting that a special effort be made to keep him supplied "wi' th' latest bluids." A member of the Committee with a sneaking regard for this type of literature took it upon himself to ransack London for penny dreadfuls, and Tam received a generous stock with regularity. "A'm no' so fond o' th' new style," he said; "the detective stoory is verra guid in its way for hame consumption, but A' prefair the mair preemative discreeptions, of how that grand mon, Deadwood Dick, foiled the machinations of Black Peter, the Scoorge of Hell Cañon. A've no soort o' use for the new kind o' stoory--the love-stoories aboot mooney. Ye ken the soort: Harild is feelin' fine an' anxious aboot Lady Gwendoline's bairthmark: is she the rechtfu' heir? Oh, Heaven help me to solve the meestry! (To be continued in oor next.) A'm all for bluid an' fine laddies wi' a six-shooter in every hand an' a bowie-knife in their teeth--it's no' so intellectual, but, mon, it's mair human!" * * * * * Tam was out one fine spring afternoon in a one-seater Morane. He was on guard watching over the welfare of two "spotters" who were correcting the fire of a "grandmother" battery. There was a fair breeze blowing from the east, and it was bitterly cold, but Tam in his leather jacket, muffled to the eyes, and with his hands in fur-lined gloves and with the warmth from his engine, was comfortable without being cozy. * * * * * Far away on the eastern horizon he saw a great cloud. It was a detached and imperial cumulus, a great frothy pyramid that sailed in majestic splendor. Tam judged it to be a mile across at its base and calculated its height, from its broad base to its feathery spirelike apex, at another mile. "There's an awfu' lot of room in ye," he thought. It was moving slowly toward him and would pass him at such a level that did he explore it, he would enter half-way between its air foundation and its peak. He signaled with his wireless, "Am going to explore cloud," and sent his Morane climbing. He reached the misty outskirts of the mass and began its encirclement, drawing a little nearer to its center with every circuit. Now he was in a white fog which afforded him only an occasional glimpse of the earth. The fog grew thicker and darker and he returned again to the outer edge because there would be no danger in the center. Gently he declined his elevator and sank to a lower level. Then suddenly, beneath him, a short shape loomed through the mist and vanished in a flash. Tam had a tray of bombs under the fuselage--something in destructive quality between a Mills grenade and a three-inch shell. He waited....