When I am recalled, I shall be very glad if the Minister of War will give you permission to come to me. You will become acquainted with a fine country and a beautiful city, where I have had the satisfaction of remaining in peace while disaster has overwhelmed so many other places."
Peace being restored, Sadi rejoined his father at Anvers and returned with him into France.
In the month of October he left the Polytechnic School, ranking sixth on the list of young men destined to service in the engineer corps, and went to Metz as a cadet sub-lieutenant at the school. Many scientific papers that he wrote there were a decided success. One is particularly referred to as very clever, a memoir on the instrument called the theodolite which is used in astronomy and geodesy.
I obtain these details from M. Ollivier, who was of the same rank as Sadi and who, later, was one of the founders of the Ecole Centrale. Among his other comrades besides M. Chasles, the learned geometrician just now referred to, was Gen. Duvivier, lamented victim of the insurrection of June 1848. I ought also to mention M. Robelin, Sadi's most intimate friend, who came to help me nurse him during his last illness, and who pub-
