What does Mr. Smith tell his secretary to say?

W: You have a telephone call, Mr. Smith.
M: Who is it?
W: He didn’t say.
M: Tell him I’m not in the office. Say I’ll be back by four o’clock.
W: All right. Hello, sir... ?
M: Yes?
W: I’m afraid he’s just stepped out of the office. May I ask who’s calling?
M: Yes, this is Edgar Davis from Boston.
W: Oh, yes, Mr. Davis. I am afraid he won’t be back until four o’clock. Could you give me your number, please.
M: Yes.