They began on their work where they had left off, and about an hour later their employer put in an appearance.
"Hard at it, eh?" he said, cheerily. "That's the way I like to see things move. Nat, I want you to go to the post office again."
"Yes, sir."
In a few minutes our hero had departed, and then Hamilton Dart turned to Harry Bray.
"Bray, here is an important document to deliver to a party living near Central Park," said he. "Deliver it, and get a receipt."
"I will, sir," answered Harry Bray, and in a minute more he, too, was gone.
An hour later there was a knock on the door, and the sick man, who had called the day before, came in.
"Is that situation still open?" he questioned, anxiously.
"Why do you ask?" demanded Hamilton Dart, abruptly.
"I was going to say that I borrowed that money from my sister."