The splendid Arabian stallion Shahwan, purchased by Lady Anne and Wilfrid Blunt in 1892, was foaled in the possession of Muhammad Sadyk Pasha, who was given his dam in foal by Ali Pasha Sharif. He is the maternal grandsire of Ibn Yashmak, through whom he finds his way into modern Egyptian pedigrees. I found the trace of Muhammad Sadyk Pasha (1832-1902). He was a senior military official — a Lewa, just like Ibrahim Khairi Pasha, owner of Badaouia –, a geographer, an explorer, and a military engineer, graduate of the Ecole Polytechnique of Paris, as well as the president of the Egyptian Geopraphic Society in his later days. He undertook four journeys to Hijaz and Muslim holy cities of Mecca and Medina, which he described in great detail in a book, “al-Rahalat al-Hijaziyah”, translated as “Journeys to Hijaz”. He was reportedly the first person to take photos of the two holy cities, which appeared in Oriental and Western publications. Muhammad Sadyk Pasha was the treasurer of the Pilgrimage (Hajj) caravan on two journeys. Click on this superb Biritish Museum link for a more complete bio, a photo of him, and a selection of his wonderful photographs. Saudi Aramco also has an article about him.