Perhaps he is after this gold.

If he is, he may have the satisfaction of knowing that he won't get it." So saying, Frank began to close and fasten the shutters which protected the windows, and while thus engaged, he caught a glimpse of the Ranchero's dark face peering at him around the corner of the house.
"If I owned this ranch," said Frank, to himself, "that fellow shouldn't stay here five minutes longer.

I'd pay him off, and tell him to leave as fast as his horse could carry him." Having satisfied himself that the windows were so well secured that no one could effect an entrance through them, Frank opened the drawer and took another good look at the money, as if he were afraid that it might have been spirited away even while he was in the room; after which he locked the desk, and hid the key under the edge of the carpet.

Then glancing about the office, to make sure that every thing was safe, he closed the door, and hurrying into his own room, he threw the key under his writing-desk, next to the wall.

Then he breathed easier.