“Dear Sir, I want to ask if Jack Minot came to see you last Friday afternoon.  He got into trouble being seen with Jerry Shannon.  He paid him some money.  Jack won’t tell, and Mr. Acton talked to him about it before all the school.  We feel bad, because we think Jack did not do wrong.  I don’t know as you have anything to do with it, but I thought I’d ask.  Please answer quick.  Respectfully yours,

“Jane Pecq”

To make sure that her despatch was not tampered with, Jill put a great splash of red sealing-wax on it, which gave it a very official look, and much impressed Bob when he received it.

“There!  Go and post it, and don’t let any one see or know about it,” she said, handing it over to Frank, who left his work with unusual alacrity to do her errand.  When his eye fell on the address, he laughed, and said in a teasing way,—­

“Are you and Bob such good friends that you correspond?  What will Jack say?”

“Don’t know, and don’t care!  Be good, now, and let’s have a little secret as well as other folks.  I’ll tell you all about it when he answers,” said Jill in her most coaxing tone.

“Suppose he doesn’t?”

“Then I shall send you up to see him.  I must know something, and I want to do it myself, if I can.”

“Look here; what are you after?  I do believe you think——­” Frank got no farther, for Jill gave a little scream, and stopped him by crying eagerly, “Don’t say it out loud!  I really do believe it may be, and I’m going to find out.”

“What made you think of him?” and Frank looked thoughtfully at the letter, as if turning carefully over in his mind the idea that Jill’s quick wits had jumped at.

“Come here and I’ll tell you.”

Holding him by one button, she whispered something in his ear that made him exclaim, with a look at the rug,—­

“No! did he?  I declare I shouldn’t wonder!  It would be just like the dear old blunder-head.”

“I never thought of it till you told me where Bob was, and then it all sort of burst upon me in one minute!” cried Jill, waving her arms about to express the intellectual explosion which had thrown light upon the mystery, like sky-rockets in a dark night.

“You are as bright as a button.  No time to lose; I’m off;” and off he was, splashing through the mud to post the letter, on the back of which he added, to make the thing sure, “Hurry up.  F.M.”

Both felt rather guilty next day, but enjoyed themselves very much nevertheless, and kept chuckling over the mine they were making under Jack’s unconscious feet.  They hardly expected an answer at noon, as the Hill people were not very eager for their mail, but at night Jill was sure of a letter, and to her great delight it came.  Jack brought it himself, which added to the fun, and while she eagerly read it he sat calmly poring over the latest number of his own private and particular “Youth’s Companion.”