"The Huns grasped the meaning of their dead spy's signal as soon as it showed in the heavens, so to speak. We lay belly-flat and held our breaths for a moment or so in silence, but we were about the only silent things for a hundred miles. Flares went up by the thousand and searchlights cut up the sky in every direction. All kinds of mysterious guns got into action and all the batteries for a hundred miles must have let drive as well. From then on, for at least two hours, the shells poured excruciating-wise into our deserted trenches without cessation,--shrapnel, high explosive, six inch, twelve inch--thousands of pounds the Huns wasted that night. "I wish you could have seen Tommy bowing to right and left of the German trenches acknowledging the applause which the Huns would have given him if they'd known the facts. On the other hand, as the Colonel observed, they might 'ave killed him. "'They'll have to pull up their socks at Krupp's to replace the shells they have blazed away in this little pantomime,' said Tommy pressing his hands to his sides. 'Star programme--heap big star programme! Phew! Oh, I wish I could stop laughing, I ain't 'ad such a laugh for years!' "'And in this little code book here,' said the old man, a hand on each of our shoulders, 'there are hundreds of little love messages we can be getting ready to surprise 'em with. Presently we'll begin to send 'em instructions to concentrate their fire on empty houses--tell 'em they are chock-full of British troops. Then they'll fairly let loose the bow-yows of war. Damme, how their gunners will gun! Oblige me by thinking of four hundred guns, pumping val-u-able shells into an empty house.' "The exquisite humour of it brought us down screaming with laughter in a tangle on the slag-heap. A searchlight broke out from the back of the Hun trenches and began searching our lines. "'They're looking for our attacking party, or the Angels of Mons,' panted the old man, his knees in a shell hole and his face in the grass. 'Well, let's get our things packed and hurry back. I think they have sent back for a fresh supply of shells. The sooner we get out of it the better. Sufficient unto the day--or night, perhaps one should say.' "Well, it's dry work talking," said McNab, wistfully surveying the interior of his empty mug. I took measures--pint measures--to allay his thirst. "Let me see now," he said; "let me see." "And did you do any signalling with the flash lamp the next night?" I timidly hinted, "I believe you mentioned that it was your intention." "Yes, we did have some fun, I can tell you, and 'twas better still next night. Once more we returned, to the slag-heap, then," McNab swept on, "we started to flash a few messages over to the German lines. They soon picked up our signals and after a brief interrogation they replied. Then they started to ask questions. 'At which part of the British line would it be wise to launch an attack?' they flashed.