Dr. Leslie at his desk ca. 1940's

After Dr. Sarah suggested one doctor in the family was enough, he moved back to New York and in 1920 Leslie became the first industrial doctor in the city. He was hired by McGraw Hill Company and eventually left medicine permanently when he decided that printing was in his blood. It was here at McGraw Hill that he first met Sol Cantor, who worked for the Carey Printing Company, located in the same building. The two men formed a partnership and created the Enmore Linotype Company. A few years later the business was bought out by Louis Statenstein and Leslie was under contract with him for four years. In 1927, he and Cantor partnered again and formed The Composing Room, Inc. In the early thirties, Leslie served as the American editor of Gebrauchsgraphik, the German art and design periodical. When the magazine folded he decided to create his own version - PM magazine. With co-editor, Percy Seitlin, the magazine became a collaborative effort in that the typesetting was done at The Composing Room, paper was donated and the presswork was done at a reduced rate.