 In 1937 Black returned to Toronto and for a short time worked for the firm Chapman and Oxley, and in 1939 formed a short-lived partnership with John B. Parkin, who had graduated in the same class as Black.In the summer of 1941 Black returned to Regina where he remained for a year.Following the outbreak of the Second World War in September 1939, Black enlisted in the Royal Canadian Navy in 1942.