Opinion by
(No. 55993;
First District (3rd Division)
October 5, 1972.
Rehearing denied March 23, 1973.
Daniel L. Houlihan, of Chicago, for appellants.
Richard L. Curry, Corporation Counsel, of Chicago, (William R. Quinlan and Thomas J. Cachor, Assistant Corporation Counsel, of counsel,) for appellees.
Opinion by