His efforts were helped by the efficiency of the print shop. Horace Hart was appointed as Controller of the Press at the same time as Gell, but proved far more effective than the Secretary. With extraordinary energy and professionalism, he improved and enlarged Oxford's printing resources, and developed "Hart's Rules" as the first style guide for Oxford's proofreaders. Subsequently, these became standard in print shops worldwide. In addition, he suggested the idea for the Clarendon Press Institute, a social club for staff in Walton Street. When the Institute opened in 1891, the Press had 540 employees eligible to join it, including apprentices. Finally, Hart's general interest in printing led to him cataloguing the "Fell Types", then using them in a series of Tudor and Stuart facsimile volumes for the Press, before ill health led to his death in 1915. By then, OUP had moved from being a parochial printer into a wide-ranging, university-owned publishing house with a growing international presence.