Marcus Wilkeson knew that the inventor was about to part with his secret unwillingly, and that he would regret it forever after.  To save him from unpleasant feelings on that score, and to maintain friendly relations between them for the future, Marcus put a stop to the reluctant disclosure.  He said: 

“Never mind it, Mr. Minford.  I know nothing of mechanical matters, and take no interest in them.  Your explanation would only be wasted on me.  Besides, it is entirely uncalled for, as I am willing to take your own opinion of the invention, and will pay you five hundred dollars for a one-tenth interest in it, if those terms will suit.”  Marcus took a keen delight in acting upon this singular impulse, and was sorry he had not said a “thousand,” when he saw the glow of happiness that irradiated the sweet face of Pet, still sitting on the stool by her father’s side.

[Illustration:  The boy bog]

“Heaven bless you, sir!” said Mr. Minford.  “You will be the means not only of relieving me and my dear child, but also of conferring the boon of a great discovery upon mankind.  But your terms are too liberal, sir.  I shall insist upon assigning one fifth of my right to you, which, mark my prediction, will prove of itself a fortune.  Furthermore, I feel that I ought, if only to show my complete confidence in you, to tell you what it is.  It is—­” Mr. Minford hesitated for a word.

“Now I beg, as a particular favor, that you won’t tell me,” said Marcus, goodhumoredly.  “If you bore me with any of those dull details, I’ll—­I’ll take back my offer.  As to the proportion of the invention which I am to have, I will accept one fifth, since you insist on it, not because I want it, but that we may not say another word about the matter.”

“As you please, sir.  But how shall I sufficiently thank you?”

Marcus, who was already overcome with the gratitude which shone from the large, soft eyes of the young girl, answered, with a laugh and a blush (he had not outgrown the habit of reddening on occasions): 

“By changing the subject.”

Mr. Minford was about to protest against this extraordinary method of thanking a benefactor, when a rap was heard at the door.

CHAPTER VII.

The boy bog.

In reply to the invitation, “Come in,” a tall boy opened the door, and started back on seeing a stranger.

“Do come in, Bog,” said Mr. Minford.  “I have good news to tell you.  This is a friend of ours, Mr. Wilkeson.  What with his running of errands, and doing little jobs for us, we really couldn’t get along without him.  Oh, walk in, Bog; you’re always welcome here.”

“Now do come in, Bog,” added the little girl, in a winning tone, rising from her stool, stepping to the door, and placing a hand on his shoulder.