They were to be trapped at once, the sooner the better, put into boxes, which were to be marked C.O.

D.and forwarded, charges paid, to the address at the bottom of the letter.
"Cod," repeated David, whose opportunities for learning how business was transacted had been very limited, "does he mean codfish ?" Don and Bert laughed heartily.
"No," said the former, as soon as he could speak.

"C.

O.D.means 'collect on delivery.'" "O," said David, in a tone of voice which showed that he did not yet fully understand.
"It is nothing to be ashamed of," said Bert; "we didn't know what the letters meant until father told us." "That's so," said Don; "how is a fellow to know a thing he has never had a chance to learn?
Now when the birds are caught, you put so many of them in a box and on each box you mark the value of its contents.
You send a notice of shipment to the man, and he will know when to look for the birds.

When they arrive he pays the amount of your bill to the express agent, and the agent forwards it to you.