"I think I'll wait until night, Fred—or at least until it is dark."
After that the boys spent the time in exploring the woods and looking over the plains beyond. They saw several wagon tracks, apparently leading to nowhere in particular, and they also found something of a cave, covered with logs and heaped-up brushwood.
"Something more to investigate," said Tom, and began to pull the brushwood away, followed by his companions. The logs followed, and there was revealed to them an opening at least twenty feet square by half that in height.
"What do you call this?" questioned Tom, as he kicked something of metal lying under a pile of dead leaves.
"It's a roller of some sort," answered Songbird. "And see, here are some cog-wheels and a lot of old shafting."
"Machinery, and quite some of it, too," murmured Dick. "They must run a regular factory of some sort here."
"I think I have solved the problem!" cried Fred. "I've read of this a number of times. This Sack Todd has a secret process of manufacturing some article and he doesn't want anybody to learn what the process is. So he has established himself here and sworn all his workmen to secrecy."
"I've heard of that myself," said Tom. "A man had a certain process of tanning leather. He kept his secret for years, until a workman got mad at him and gave the thing away."
Dick was inspecting the machinery with care. It was worn out and rusted, and hard to make out just what it was.
"Unless I am mistaken, these are parts of a printing press," said the eldest Rover.