"We'll have the shrapnel on our heads when they shorten the range," observed one man.

"No fear," replied Peter. "They'll be afraid of the stuff falling on their own thick skulls. Now, Malcolm, stand by. Hurrah, there go the white-livered Landsturmers!"

Which was a fact. Panic-stricken, the grey-bearded and bald-headed guards deserted their posts and bolted precipitately, as if by running they could outstrip a squadron of biplanes moving at a hundred miles an hour. The dogs, too, had changed their tune--instead of barking they were whining dolefully.

Right overhead the leading aircraft of the V formation seemed to swoop. The Huns, as Peter Carr had predicted, had ceased fire, and were tearing away to take up a fresh position whence they could serve their guns without fear of the earth-returning shrapnel peppering their gunners.

An ear-splitting roar announced that the strafing of Düren had commenced. A powerful bomb had landed fairly in the centre of the principal factory, blowing out the walls and sending showers of bricks, stones, tiles, and timber far and wide.

It was the first of several. The very ground seemed to emit fire, the earth trembled under the terrific concussions, dense clouds of smoke were rising up from the disintegrated buildings, while the din was indescribably awful.

"Now's our time!" roared the Sergeant. "No. 2 hut's empty. Good luck, chaps!"

Into the open the men ran, not away from the adjoining and badly-shattered factory but towards it. As they expected, some of the bombs had fallen wide of the building and had blown gaps in the double fence.

"Keep together, Malcolm," shouted Peter.

"You bet," replied his brother.