PROFESSOR ROBERT S. BALL, LL. D., F. R. S., ANDREWS PROFESSOR OF ASTRONOMY IN THE UNIVERSITY OF DUBLIN, AND ROYAL ASTRONOMER OF IRELAND.

I fear my experience can be of little use to you. I have never smoked except once—when at school; I then got sick, and have never desired to smoke since. I have not paid particular attention to the subject, but I have never seen anything to make me believe that tobacco was of real use to intellectual workers. I have known of people being injured by smoking too much, but I never heard of anyone suffering from not smoking at all.

ROBERT S. BALL.
February 13, 1882.