A little later the authorities took charge of matters, entering the cave and taking possession of a very complete though small printing plant, and numberless bogus tickets. Constables were sent to look for the three men. The old man was arrested and taken to jail, and Bombee, his son, who would not be separated from him, went with him. But before Jason was taken away, he told enough to make the mystery clear.
He was an expert printer, it seemed, and had fallen in with a band of men who planned to flood the country with bogus railroad and theatrical tickets. They had set up their plant in the cave, the existence of which they had learned by accident and kept secret.
There were three entrances to the cave. One was in the side of the hill, where the men had put up a shack in order to conceal the opening. The second was the one discovered by accident by Cora. This was not used, being too small. And the third was through the bungalow and the passage.
This passage, the secret sliding door in the floor, and the cement door that blocked the passage (it developed later) had been constructed by the actor who formerly owned the bungalow. Just what his object was no one knew, but his unbalanced mind probably built a romance about the great dark hole. The cave was then used for nothing, but it admirably suited the purposes of the ticket men who fitted it up as they wished.
To it they brought their machinery and began issuing tickets, Jason, aided by the half-witted Bombee, doing the printing, while the others distributed the product. It was the rumble and clank of the gasoline engine and presses that made the queer trembling sounds heard by the girls and boys. The rocky cave acted as a sort of telephone, or sound box, and sometimes the noises would be louder than others. The fact that the engine stood on a strata of rock upon which the bungalow was constructed accounted for the trembling and vibration of the building.
“We did the printing when you folks were away from the bungalow at most times,” said old Jason. “We found out when you were gone by means of the secret passage. But sometimes we had to work on a rush order when you were on hand.”
“Then is when we heard the noise,” said Jack.
“But who upset the furniture, and took our things?” asked Cora.
“Oh, that was Bombee,” said the old man. “I could not always watch him, and he would slip away, open the secret door of the passage and get up into the bungalow through the floor. He is very mischievous, but gentle. He likes to upset chairs and tables. He used to do that trick, among others, in a theatre where he used to show as a human ape. He didn’t look unlike an ape, you see.”
“He took your ribbons and things, too. They are in the cave. I thought they came from your bungalow, but I did not dare return them. Once he brought in a flashlight.”