Sure enough, the light had flashed out once in the blackness of the night, and then as suddenly disappeared.

The boys began hauling in on the copper wire, winding it again on the reel.

"Who's next?" asked Frank, as the last of the cable was being re-wound.

"Eenie, meenie, minie, mo," Jerry began to count out, when Joe suddenly interrupted.

By ten feet of heavy twine Lieutenant Mackinson had tied the spurs to the car so that they would dangle within reach of the lads on the ground. Attached to them was a note, which read:

"Easy landing on soft slope. Let Slim come next before wire is weakened, because he is the heaviest. All can make it safely."

And so Slim, not entirely a.s.sured, and breathing somewhat heavily as he contemplated the distance he had to fall if the telegraph wire should break, was the next to climb a-straddle the crude "air-line" trolley, on its second trip to the opposite mountain.

In a few moments the light flashed out again and then disappeared, while Joe, Jerry and Frank hauled in on the cable to which the car was attached.

By mutual agreement it was arranged that Frank should be the next to go over, after which they would send the portable wireless, followed by Jerry, and finally Joe.

Lads of less courage never would have attempted such a perilous escape, but they made it without a single mishap. It was not until Joe, the last of the party, was just coming to a stop in the outstretched arms of his friends, that the Germans below, and on what was now the opposite mountain, seemed to sense something going on--or perhaps had seen the mysterious blinking of the flashlight--and let go a distant and futile volley of shots.

"No use, Boche," called the lieutenant mockingly, "we're out of your range. And now, having escaped you, we'll see what we can do to hara.s.s you."

Saying which he began opening up the pack-set wireless, while two of the others set up the umbrella antenna.

Lieutenant Mackinson began tapping off the headquarters call. It might have been the slightly nearer position they were in, or, so far as they knew, headquarters might have moved meanwhile, but in a very short time the operator there was responding.

The young officer gave an accurate account of the operations of the Germans, and particularly of their artillery. Headquarters thanked them, told them to stay until morning where they were, and then ask for further orders.

In less than half an hour the boom of heavy guns from the westward told them that they had given their information in time.

American artillery was dropping a rain of sh.e.l.ls into the cuts in the mountain through which the Germans had to emerge with their guns to do any damage! Their whole plan, so carefully carried out, had been defeated!

CHAPTER XVIII

SLIM GOODWIN A PRISONER

"If I had a good rifle I could 'pot' half a dozen of them from here,"

said Jerry the following morning as he and the rest, standing back among the trees of the mountain in which they had sought safety, watched two long, converging lines of German soldiers marching back in the direction whence they had come on the preceding day.

"And we owe them that much for that nice, nifty little night trapeze act we had to do through s.p.a.ce on their account," added Slim.

"Not to mention the wrecked tractor," put in Frank.

"Well," spoke Lieutenant Mackinson, calling them to the business of the day, "I guess we can make a report to headquarters now--and a good one, too."

With which he opened up the wireless and began repeating the call letters.

When headquarters had responded, the lieutenant gave them the glad tidings of the Boche retreat. That done, he proceeded to give the details of the wrecking of the tractor and of their escape to the second mountain.

"Ought to be aviators," the operator at headquarters came back at him on his own account, and then added: "Wait for orders."

These came a few minutes later.

"Divide as follows: Lieutenant and two men return here; other two go forward at safe distance with portable, and report to-night."

Lieutenant Mackinson read them the message.

"Well," he asked, "which two are to accompany me back, and which two are to stay on the heels of the Boches?"

"I've got a scent like a deerhound," averred Slim.

"And I was born to be a scout," declared Jerry.

"You two spoke first," announced the lieutenant pleasantly, "so I guess that shall be your end of it, if that's what you want."

"Fine!" exclaimed Jerry and Slim in unison.

"Anyway," added the lieutenant, "I guess there'll be enough serious work for the rest of us when we get back. For instance," winking at the others, "there's that smashed tractor, Frank, that you will have to explain."

"Not so long as you were in charge of the party," Hoskins retorted quickly. And Lieutenant Mackinson, unable to determine whether the remark was a facetious evasion of responsibility or an indirect compliment to himself, on the ground that no act of his would be questioned, pursued his bantering no further.

"I guess," he said, "that Joe, Frank and I had better start back at once. You two will have to wait here some time before you can begin trailing that army. I'm sorry we can't stay with you, but I feel that we ought to report back as soon as possible."

And so the three of them began the preparations for their return, while Jerry and Slim watched and studied the movements of the regiments they were to follow.

"They seem to be pretty well tired out," said Slim at last. "Guess they didn't have any sleep at all last night."

"We're going to find it pretty heavy tramping through that snow, too,"

Jerry answered. "And with the wireless and rations we'll be carrying a hefty weight."

"Well, boys; we're off," announced Lieutenant Mackinson, and the separating parties shook hands all around. "Take care of yourselves," he admonished, "and we'll look for you back by to-morrow."

The officer, Joe and Frank started off on their long tramp back to camp, and Jerry and Slim watched them until they were out of sight.

"That looks like the last regiment of the Germans going over the opposite hill there, too," said Jerry, as they turned to observe the enemy army. "We can start in a short while."

And in half an hour, Jerry carrying the heavy pack-set and Slim toting the equally weighty rations and incidentals, they set off on the Boches'

trail.

Out in the open, and especially in the mountains, distances are deceptive. Jerry and Slim learned this when they had been traveling for two hours, and the point where they had seen the last German disappear over a hilltop seemed as far away as when they started.

"Ever travel along in a train at night watching the moon, and notice how it seemed to move right along with you?" asked Jerry.

"Lots of times," answered Slim, as he puffed along, "Why?"