Left to himself, Rodney could think soberly of his plight.  He could not foresee whether his captivity would be brief or prolonged.

After a time the spirit of curiosity seized him.  He felt tempted to explore the cavern in which he was confined.  He took a lamp, and followed in a direction opposite to that taken by his captors.

The cave he found was divided into several irregularly shaped chambers.  He walked slowly, holding up the lamp to examine the walls of the cavern.  In one passage he stopped short, for something attracted his attention—­something the sight of which made his heart beat quicker and filled him with excitement.

CHAPTER XXXIV.

RODNEY’S DISCOVERY.

There was a good reason for Rodney’s excitement.  The walls of the subterranean passage revealed distinct and rich indications of gold.  There was a time, and that not long before, when they would have revealed nothing to Rodney, but since his residence at Oreville he had more than once visited the mines and made himself familiar with surface indications of mineral deposit.

He stopped short and scanned attentively the walls of the passage.

“If I am not mistaken,” he said to himself, “this will make one of the richest mines in Montana.  But after all what good will it do me?  Here am I a prisoner, unable to leave the cave, or communicate with my friends.  If Mr. Pettigrew knew what I do he would feel justified in paying the ransom these men want.”

Rodney wondered how these rich deposits had failed to attract the attention of his captors, but he soon settled upon the conclusion that they had no knowledge of mines or mining, and were ignorant of the riches that were almost in their grasp.

“Shall I enlighten them?” he asked himself.

It was a question which he could not immediately answer.  He resolved to be guided by circumstances.

In order not to excite suspicion he retraced his steps to the apartment used by his captors as a common sitting room—­carefully fixing in his mind the location of the gold ore.

We must now follow the messenger who had gone to Oreville with a letter from Rodney’s captors.

As instructed, he left his horse, or rather Rodney’s, tethered at some distance from the settlement and proceeded on foot to the Miners’ Rest.  His strange appearance excited attention and curiosity.  Both these feelings would have been magnified had it been known on what errand he came.

“Where can I find Mr. Jefferson Pettigrew?” he asked of a man whom he saw on the veranda.

“At the Griffin Mine,” answered the other, removing the pipe from his mouth.

“Where is that?”

“Over yonder.  Are you a miner?”

“No.  I know nothing about mines.”

“Then why do you want to see Jefferson?  I thought you might want a chance to work in the mine.”