Ned showed the paper with the advertisement in it.
"I wondered where I had lost that," Frank said. "Well, boys, I'm going to tell you my secret."
"Have some coffee before you begin," suggested Fenn, as he handed Frank a steaming cupful. "It's only warmed up, but it's good."
The exhausted boy drank it, and ate some bread. Then having changed some of his muddy clothes for garments loaned him by his chums, Frank began:
"You guessed rightly, I did go to the sanitarium, and I got the position. But I don't believe any of you can guess why."
"Was it to get experience about crazy persons?" asked Ned.
"I went there to plan to rescue my father," said Frank, quietly.
The announcement was so startling that the three chums could only look at one another. Then they glanced back at Frank to see if he was in earnest. Ned, for a moment, had an idea that his original theory was right, and that Frank's mind was affected. But one look at the boy showed that, though he labored under the stress of excitement, he knew what he was talking about.
"Your father!" exclaimed Bart. "I thought he was—"
"You thought he was dead; so did I," Frank broke in. "That is, until recently. It's a long story, and I haven't got it all straight in my mind yet. One thing I am sure of is that my father is detained in that asylum against his will, and I am going to rescue him!"