When he got back to the aerodrome that night he found that the bombing of hospitals was the subject which was exciting the mess to the exclusion of all others. "It's positively ghastly that a decent lot of fellows like German airmen can do such diabolical things," said Blackie; "we are so helpless. We can't go along and bomb his collecting stations." "Fritz's material is deteriorating," said a wing commander; "there's not enough gentlemen to go round. Everybody who knows Germany expected this to happen. You don't suppose fellows like Boltke or Immelmann or Richthoven would have done such a swinish thing?" That same night One-Three-One was bombed again, this time with more disastrous effects. One of the raiders was brought down by Blackie himself, who shot both the pilot and the observer, but the raid was only one of many. The news came through in the morning that a systematic bombing of field hospitals had been undertaken from Ypres to the Somme. At two o'clock that afternoon Blackie summoned his squadron. "There's a retaliation stunt on to-night," he explained; "we are getting up a scratch raid into Germany. You fellows will be in for it. Tam, you will be my second in command." * * * * * At ten o'clock that night the squadron rose and headed eastward. The moon was at its full, but there was a heavy ground mist, and at six thousand feet a thin layer of clouds which afforded the raiders a little cover. Tam was on the left of the diamond formation, flying a thousand feet above the bombers, and for an hour and a half his eyes were glued upon the signal light of his leader. Presently their objective came into sight: a spangle of lights on the ground. You could follow the streets and the circular sweep of the big Central Platz and even distinguish the bridges across the Rhine, then of a sudden the lights blurred and became indistinct, and Tam muttered an impatient "Tchk," for the squadron was running into a cloud-bank which might be small but was more likely to be fairly extensive. They were still able to distinguish the locality, until three spurts of red flame in the very center of the town marked the falling of the first bombs. Then all the prominent lights went out. There were hundreds of feeble flickers from the houses, but after a while these too faded and died. In their place appeared the bright, staring faces of the searchlights as they swept the clouds. Tam saw the flash of guns, saw the red flame-flowers of the bombs burst to life and die, and straining his eyes through the mist caught the "Return" signal of his leader. He banked round and ran into a thicker pall of fog and began climbing. As he turned he saw a quick, red, angry flash appear in the clouds and something whistled past his head. The guns had got the altitude of the bombers to a nicety and Tam grinned.