He watched them with round eyes of wonder and interest, however,--when he did not think they were watching him.

And in time he came to know not a little about them and about the strange ways in which they passed their time.
There was the greenhouse man.

It would be pleasant to spend one's day growing plants and flowers--but not under that hot, stifling glass roof, decided David.

Besides, he would not want always to pick and send away the very prettiest ones to the city every morning, as the greenhouse man did.
There was the doctor who rode all day long behind the gray mare, making sick folks well.

David liked him, and mentally vowed that he himself would be a doctor sometime.