Snatching up in her arms the now awakened child, the woman gazed for a moment into its face, which she covered with kisses. Then the herb-gatherer looked over to the dead, limp body of the great condor, and from thence to Tom.

In another moment the woman had rushed forward, and knelt at the feet of the young inventor. Holding the baby in one arm, in her other hand the woman seized Toms and kissed it fervently, at the same time pouring forth a torrent of impassioned language, of which Tom could only make out a word now and then. But he gathered that the woman was thanking him for having saved the child.

"Oh, that's all right," Tom said, rather embarrassed by the hand-kissing. "It was an easy shot."

An Indian came bursting through the bushes, evidently the woman's husband by the manner in which she greeted him, and Tom recognized the newcomer as one of the tunnel workers. There was some quick conversation between the husband and wife, in which the latter made all sorts of motions, including in their scope Tom, his rifle, the dead condor and the now smiling baby.

The man took off his hat and approached Tom, genuflecting as he might have done in church.

"She say you save baby from condor," the man said in his halting English. "She t'ank you--me, I t'ank you. Bird see babe in deer skin--t'ink um dead animal. Maybe so bird carry baby off, drop um on sharp stone, baby smile no more. You have our lives, senor! We do anyt'ing we can for you."

"Thanks," said Tom, easily. "I'm glad I happened to be around. I supposed condors only went for things dead, but I reckon, as you say, it mistook the baby in the deer skin for a dead animal. And I guess it might have carried your little one off, or at least lifted it up, and then it might have dropped it far enough to have killed it. It sure is a big bird," and Tom strolled over to look at what he had bagged.

The condor of the Andes is the largest bird of prey in existence. One in the Bronx Zoo, in New York, with his wings spread out, measured a little short of ten feet from tip to tip. Measure ten feet out on the ground and then imagine a bird with that wing stretch.

This same condor in the park was made angry by a boy throwing a feather boa up into the air outside the cage. The condor raised himself from the ground, and hurled himself against the heavy wire netting so that the whole, big cage shook. And the breeze caused by the flapping wings blew off the hats of several spectators. So powerful was the air force from the condor's wings that it reminded one of the current caused when standing behind the propellers of an aeroplane in motion. The condor rarely attacks living persons or animals, though it has been known to carry off big sheep when driven by hunger.

It was one of these animals Tom Swift had shot with his electric rifle.

"We do anyt'ing you want," the man gratefully repeated.

"Well, I've got about all I want," Tom said. "But if you could tell me where those ten missing men are, and how they got out of the tunnel, I'd be obliged to you."

The woman did not seem to comprehend Tom's talk, but the man did. He started, and fear seemed to come over him.

"Me--I--I can not tell," he murmured.

"No, I don't suppose you can," said Tom, musingly. "Well," it doesn't matter, I guess I'll have to cross it off my books. I'll never find out."

Again the Indian and his wife expressed their gratitude, and Tom, after letting the little brown baby cling to his finger, and patting its chubby cheek, went on his way with Koku.

"Well, that was some excitement," mused Tom, who made little of the shot itself, for the condor was such a mark that he would have had to aim very badly indeed to miss it. And perhaps only the electric rifle could have killed quickly enough to prevent the baby's being injured in some way by the big bird, even though it was dying.

"Master heap good shot!" exclaimed Koku, admiringly.

The tunnel work went on, though not so well as when Tom's explosive was first used. The rock was indeed getting harder and was not so easily shattered. Tom made tests of the pieces he had obtained from the outcropping ledge on the mountain where he had shot the condor, and decided to make a change in the powder.

Shipments were regularly received from Shop ton, Mr. Swift keeping things in progress there. Mr. Damon's business was going on satisfactorily, and he lent what aid he could to Tom. As for Professor Bumper he kept on with his search for the lost city of Pelone, but with no success.

The scientist wanted Tom and Mr. Damon to go on another trip with him, this time to a distant sierra, or fertile valley, where it was reported a race of Indians lived, different from others in that region.

"It may be that they are descendants from the Pelonians," suggested the professor. Tom was too busy to go, but Mr. Damon went. The expedition had all sorts of trouble, losing its way and getting into a swamp from which escape was not easy. Then, too, the strange Indians proved hostile, and the professor and his party could not get nearer than the boundaries of the valley.

"But the difficulties and the hostile attitude of these natives only makes me surer that I am on the right track," said Mr. Bumper. "I shall try again."

Tom was busy over a problem in explosives one day when he saw Tim Sullivan hurrying into the office of the two brothers. The Irishman seemed excited.

"I hope there hasn't been another premature blast," mused Tom. "But if there had been I think I'd have heard it."

He hastened out to see Job and Walter Titus in excited conversation with Tim.

"They didn't come out, an' thot's all there is to it," the foreman was saying. "I sint thim in mesilf, and they worked until it was time t' set off th' blast. I wint t' get th' fuse, an' I was goin' t' send th' black imps out of danger, whin--whist--they was gone whin I got back--fifteen of 'ern this time!"

"Do you mean that fifteen more of our men have vanished as the first ten did?" asked Job Titus.

"That's what I mean," asserted the Irishman.

"It can't be!" declared Walter.

"Look for yersilf!" returned Tim. "They're not in th' tunnel!"

"And they didn't come out?"

"Ask th' time-keeper," and Tim motioned to a young Englishman who, since the other disappearance, had been stationed at the mouth of the tunnel to keep a record of who went in and came out.

"No, sir! Nobody kime hout, sir!" the Englishman declared. "Hi 'aven't been away frim 'ere, sir, not since hi wint on duty, sir. An' no one kime out, no, sir!"

"We've got to stop this!" declared Job Titus.

"I should say so!" agreed his brother.

With Tom and Tim the Titus brothers went into the tunnel. It was deserted, and not a trace of the men could be found. Their tools were where they had been dropped, but of the men not a sign.

"There must be some secret way out," declared Tom.

"Then we'll find it," asserted the brothers.

Work on the tunnel was stopped for a day, and, keeping out all natives, the contractors, with Tom and such white men as they had in their employ, went over every foot of roof, sides and floor in the big shaft. But not a crack or fissure, large enough to permit the passage of a child, much less a man, could be found.

"Well, I give up!" cried Walter Titus in despair. "There must be witchcraft at work here!"

"Nonsense!" exclaimed his brother. "It's more likely the craft of Blakeson & Grinder, with Waddington helping them."

"Well, if a human agency made these twenty-five men disappear, prove it!" insisted Walter.

His brother did not know what to say.

"Well, go on with the work," was Job's final conclusion. "We'll have one of the white men constantly in the tunnel after this whenever a gang is working. We won't leave the natives alone even long enough to go to get a fuse. They'll be under constant supervision."

The tunnel was opened for work, but there were no workers. The morning after the investigation, when the starting whistle blew there was no line of Indians ready to file into the big, black hole. The huts where they slept were deserted. A strange silence brooded over the tunnel camp.

"Where are the men, Serato?" asked Tom of the Indian foreman.

"Men um gone. No work any more. What you call a hit."

"You mean a strike?" asked Tom.

"Sure--strike--hit--all um same. No more work--um 'fraid!"