"That I don't know, Son. I was seated at the table with the open bag beside me, and was looking over some of the documents I had brought from the safe deposit vault in Wichita Falls when I heard a noise behind me near the door. I was just about to get up to see what it meant, when all of a sudden I received a terrible crack on the back of the head. I turned around, and then somebody aimed another blow at me that caught me on the left temple. Then everything seemed to dance before my eyes, and I guess I must have gone down in a heap on the floor. And that's all I knew until I found you supporting me and bathing my forehead."
"It must have been those oil-well fellows!" ejaculated Fred.
"I think I see a light!" almost shouted Jack. "Nappy and Slugger were in this plot. They made us go away out of town just so we wouldn't be here with my dad when the other fellows attacked him!"
"I guess you're right," answered Randy.
"What's this you are saying?" questioned Dick Rover, rather feebly.
In a few words the boys explained the trick Nappy Martell and Slugger Brown had played on them.
"Yes, I guess you are right. It must have been a part of the game," said Jack's father. "And are you sure my bag and everything that was in it are gone?"
"Yes, there isn't a single paper in this room," answered Jack. "And when we came up we found the door to your room locked, so it isn't likely they are there."
"They must have dug out the minute they knocked me over and got the papers," answered Dick Rover. "Probably they were afraid you or somebody else might come up and catch them at their dastardly work. As it is, it is queer somebody didn't see them."
"There happens to be no one down in the office but the young clerk, and he's half asleep," answered Randy. "Besides that, those fellows may have come in by the back way. Did you catch sight of them at all?"