"What! you have an answer already?"

"Yes, aunty."

The old woman took the letter, opened it and read:

"Madam: I saw your advertisement. I will call upon you. When a card is presented with the name of the undersigned you will know it is the detective.

"Yours,

"Oscar Dunne."

"Well, I declare," exclaimed the old lady; "he will call on us."

"But how will he know where to call, aunty; you did not give your address in the advertisement."

"That is so. I had forgotten that. Why, how will he know where to call. I fear I have made a mistake. A man who is as big a dunce as that can be of no service to us."