The projectile was slowed up to permit the two professors to make some notes regarding a particularly large and deep crater, and a few minutes later when Mark, who was in the engine room, attempted to speed up the Cordite motor it would not respond.
"Humph! I wonder what"s wrong?" he asked of Jack.
"Better call Mr. Roumann, and not try to fix it yourself," suggested his chum, when, in response to various movements of the lever, the machine seemed to go slower and slower.
The German came in answer to the summons.
"Ha!" he exclaimed, "that motor is broken again. We shall have to stop once more for repairs. I shall need to take it all apart, I fear. Get me the negative plate remover, will you, Mark?"
The lad went to the tool chest for it. He opened the lid and fumbled about inside.
"It doesn"t seem to be here," he announced.
"What! the negative plate remover not there?" cried the professor.
"Why, it must be. It is one of the new tools we got, and it has not been used for anything; has it?".
"Oh, by Jinks!" cried Jack suddenly.
"What"s the matter?" asked his chum.
"That plate remover! Don"t you remember you and I had it when we were fixing the pipes outside the projectile, when we had the other breakdown? We must have left it back there on the ground."
Jack and his chum gazed blankly at each other.
"I guess we did," admitted Mark dubiously.
"And it is the only one we have," said Mr. Roumann. "We need it very much, too, for the projectile can"t very well be moved without it."
"How can we get it?" asked Jack. "I"m sorry. It was my fault."
"It was as much mine as yours," a.s.serted Mark. "I guess it"s up to us to go back after it. It isn"t far. We can easily walk it."
There seemed to be nothing else to do, and, after some discussion, it was decided to have the two boys walk back after the missing tool, which was a very valuable one.
"Take fresh life-torches with you," advised Mr. Henderson, "and you had better carry some food with you. It may be farther back than you think, and you may get hungry."
"I guess it will be a good thing to take some lunch along," admitted Jack. "And some water, too. We can"t get a drink here unless we come to a spring, and we haven"t seen any since we arrived."
"I"ll go with you, if you don"t mind," said Andy. "I may see something to shoot."
The three of them, each one carrying a freshly charged vapor-torch, a basket of food and a bottle of water, started off, well wrapped in their fur coats. Andy had a compa.s.s to enable them to make their way back to where the tool was left, for, amid the towering peaks and the valley-like depressions, very little of the level surface of the moon could be seen at a time.
They walked on for several hours, every now and then hoping that they had reached the place where the projectile had been halted, and where they expected to find the tool. But so many places looked alike that they were deceived a number of times.
At length, however, they reached the spot and found the instrument where Jack had carelessly dropped it. They picked it up and turned to go back, when Andy Sudds saw a large crater off to one side.
"Boys, I"m going to have a look down that," he said. "It may contain a bear or wildcat, and I can get a shot."
"Guess there isn"t much danger of a bear being on the moon," said Mark, but the old hunter leaned as far over the edge of the crater as he dared.
"No, there"s nothing here," he announced, with almost a sigh, and he straightened up. As he did so there came a tinkling sound, as if some one had dropped a piece of money.
"What"s that?" asked Jack.
"By heck! It"s the compa.s.s!" cried Andy. "It slipped from my pocket when I stooped over. Now it"s gone!"
There was no question of that. They could hear the instrument tinkling far down in the unfathomable depths, striking from side to side of the crater as it went down and down.
"We"ll never see that again," spoke Mark dubiously. "Can we get back to the projectile without it?" asked Jack.
"Oh, I fancy I can pick my trail back," answered the hunter. "It isn"t going to be easy, for there are no landmarks to guide me, but I"ll do my best. I ought to have known better than to put a compa.s.s in that pocket."
It was not with very light hearts that they started back, and for a time they went cautiously. Then, as they seemed to get on familiar ground, they increased their pace and covered several miles.
"Say," remarked. Jack, as he sat down on a big stone. "I don"t know how the rest of you feel, but I"m tired. We"ve come quite a distance since we picked up that tool."
"Yes, farther than it took us to find it after we left the projectile,"
added Mark. "I wonder if we"re going right?"
The two boys looked at Andy. He scratched his head in perplexity.
"I can"t be sure, but it seems to me that we came past here," he said.
"I seem to remember that big rock."
"There are lots like it," observed Jack.
"Suppose we try over to the left," spoke Mark, after they had rested for ten minutes.
They swerved in that direction, and, after keeping on that trail for some time, and becoming more and more convinced that it was the wrong one, they turned to the right. That did not bring them to familiar ground, and there was no sight of the projectile.
"Let"s go straight ahead," suggested Andy, after a puzzled pause. "I think that will be best."
"Well, which way is straight ahead?" asked Mark.
"That"s so, it is hard to tell," admitted the hunter. "I wish I hadn"t lost that compa.s.s."
They wandered about for an hour longer. They could seem to make no progress, though they covered much ground. Suddenly Jack called out:
"Say, we"ve been going around in a circle!"
"In a circle?" asked Mark.
"Yes," went on his chum. "Here"s the very rock I sat down on a while ago. I remember it, for I scratched my initials on it."
Jack pointed out the letters. There was no disputing it. They had made a complete circle. For a moment they maintained silence in the face of this alarming fact. Then Mark exclaimed:
"I guess we"re lost!"