His autograph quest cost him stationery, postage, car-fare--all outgo.

But it had brought him no income, save a rich mental revenue.

And the boy and his family needed money.

He did not know, then, the value of a background.
He was thinking along this line in a restaurant when a man sitting next to him opened a box of cigarettes, and taking a picture out of it threw it on the floor.

Edward picked it up, thinking it might be a "prospect" for his collection of autograph letters.