After holding an appointment in England for a brief period as ADC to Wood, who was now General Officer Commanding Eastern District, he rejoined the Egyptian Army in 1886 as assistant military secretary to Sir Francis Grenfell. He took part in the operations on the Sudan frontier in 1889, including the engagement at Toski and in the further operations in 1891, being present at the capture of Tokar. His principal work was in the intelligence branch, of which he became assistant adjutant-general in 1888 and director in 1892. A master of Arabic, his knowledge of the country, the examination of prisoners, refugees and others from the Sudan, and the study of documents captured from the Dervishes enabled him to publish in 1891 "Mahdiism and the Egyptian Sudan", an authoritative account of the rise of the Muhammad Ahmad and of subsequent events in the Sudan up to that date. In 1894 he was governor of Suakin. He was promoted to brevet lieutenant colonel on 18 November 1896.