I opened the envelope and read: Roscoe Paine.
Sir: The enclosed is in payment for your work.

No receipt is necessary.
Yours truly, B.VICTOR CARVER.
The "enclosed" was a five-dollar bill.
I stood staring at the note.

Then I began to laugh.
"What's the joke ?" asked Dorinda, who had not taken her eyes from my face.
"This," said I, handing her the money.

She looked at it in astonishment.
"Um-hm," she said, drily.

"Well, I--well, a five-dollar bill may be a joke to you, but _I_ ain't familiar enough with one to laugh at it.