 As an activist for penal reform, he visited not only the continent of Europe, but Egypt, Australia, Tasmania, Canada, and the United States.He advocated in particular for more prison visitors, and lecturers.Tallack was one of the many critics of the prison administrator Edmund Frederick Du Cane, who included the Home Secretary H. H. Asquith and the prison chaplain William Douglas Morrison, but also found some emollient words for him, in 1894.