When I was in college 1957-1961, the "campus security" consisted of a night watchman and fire guard. He carried a leather covered octagonal shaped clock on a cross shoulder strap. In each building on every floor was a little [[maybe 2" X 4") metal box with a certain shaped "key" on a chain inside it. He would put that into a hole on the clock and twist it. At the end of his shift, there was a "timecard" type strip which the clock printed mechanically and which showed the times he visited each of the numbered stations during his shift.