"Now," remarked Tom, once they were back again in their camp, "we must go about this trip to the cavern in a way that will cause no suspicion over there as to what our object is," and he nodded in the direction of the quarters of his rival.  
"Do you mean to go off quietly?" asked Ned.
 
"Yes. And to keep the work going on here, at these shafts," put in the scientist, "so that if any of their spies happen to come here they will think we still believe the buried city to be just below us. To that end we must keep the Indians digging, though I am convinced now that it is useless."
 
Accordingly preparations were made for an expedition into the jungle under the leadership of Goosal. Tal had not sufficiently recovered from the jaguar wounds to go with the party, but the old man, in spite of his years, was hale and hearty and capable of withstanding hardships.
 
One of the most intelligent of the Indians was put in charge of the digging gangs as foreman, and told to keep them at work, and not to let them stray. Tolpec, whose brother Tom had tried to save, proved a treasure. He agreed to remain behind and look after the interests of his friends, and see that none of their baggage or stores were taken.
 
"Well, I guess we're as ready as we ever shall be," remarked Tom, as the cavalcade made ready to start. Mules carried the supplies that were to be taken into the jungle, and others of the sturdy animals were to be ridden by the travelers. The trail was not an easy one, Goosal warned them.
 
Tom and his friends found it even worse than they had expected, for all their experience in jungle and mountain traveling. In places it was necessary to dismount and lead the mules along, sometimes pushing and dragging them. More than once the trail fairly hung on the edge of some almost bottomless gorge, and again it wound its way between great walls of rock, so poised that they appeared about to topple over and crush the travelers. But they kept on with dogged patience, through many hardships.
 
To add to their troubles they seemed to have entered the abode of the fiercest mosquitoes encountered since coming to Honduras. At times it was necessary to ride along with hats covered with mosquito netting, and hands encased in gloves.
 
They had taken plenty of condensed food with them, and they did not suffer in this respect. Game, too, was plentiful and the electric rifles of Tom and Ned added to the larder.
 
One night, after a somewhat sound sleep induced by hard travel on the trail that day, Tom awoke to hear some one or something moving about among their goods, which included their provisions.
 
"Who's there?" asked the young inventor sharply, as he reached for his electric rifle.
 
There was no answer, but a rattling of the pans.
 
"Speak, or I'll fire!" Tom warned, adding this in such Spanish as he could muster, for he thought it might be one of the Indians. No reply came, and then, seeing by the light of the stars a dark form moving in front of the tent occupied by himself and Ned, Tom fired.
 
There was a combined grunt and squeal of pain, then a savage growl, and Ned yelled:
 
"What's the matter, Tom?" for he had been awakened, and heard the crackle of the electrical discharge.
 
"I don't know," Tom answered. "But I shot something—or somebody!"
 
"Maybe some of Beecher's crowd," ventured his chum. But when they got their electric torches, and focused them on the inert, black object, it was found to be a bear which had come to nose about the camp for dainty morsels.
 
Bruin was quite dead, and as he was in prime condition there was a feast of bear meat at the following dinner. The white travelers found it rather too strong for their palates, but the Indians reveled in it.
 
It was shortly after noon the next day, when Goosal, after remarking that a storm seemed brewing, announced that they would be at the entrance to the cavern in another hour.
 
"Good!" cried Professor Bumper. "At last we are near the buried city."
 
"Don't be too sure," advised Mr. Damon, "We may be disappointed. Though I hope not for your sake, my dear Professor."
 
Goosal now took the lead, and the old Indian, traveling on foot, for he said he could better look for the old landmark that way than on the back of a mule, walked slowly along a rough cliff.
 
"Here, somewhere, is the entrance to the cavern," said the aged man. "It was many years ago that I was here—many years. But it seems as though yesterday. It is little changed."
 
Indeed little did change in that land of wonders. Only nature caused what alterations there were. The hand of man had long been absent.
 
Slowly Goosal walked along the rocky trail, on one side a sheer rock, towering a hundred feet or more toward the sky. On the other side a deep gash leading to a great fertile valley below.
 
Suddenly the old man paused, and looked about him as though uncertain. Then, more slowly still, he put out his hand and pulled at some bushes that grew on a ledge of the rock. They came away, having no depth of earth, and a small opening was disclosed.
 
"It is here," said Goosal quietly. "The entrance to the cavern that leads to the burial place of the dead, and the city that is dead also. It is here."
 
He stood aside while the others hurried forward. It took but a few minutes to prove that he was right—at least as to the existence of the cavern—for the four men were soon peering into the opening.
 
"Come on!" cried Tom, impetuously.
 
"Wait a moment," suggested the professor, "Sometimes the air in these places is foul. We must test it." But a torch one of the Indians thr............