From 7 to 21 July, Dumas commanded the invading army's cavalry as it marched south from Alexandria to Cairo. Conditions of heat, thirst, fatigue, and lack of supplies for the troops on the desert march were harsh; there were a number of suicides. While camped in Damanhour, General Dumas met with several other generals (Lannes, Desaix, and Murat). They vented criticisms of Napoleon's leadership and discussed the possibility of refusing to march beyond Cairo. Dumas soon participated in the Battle of the Pyramids (following which he chased retreating Mameluke horsemen) and the occupation of Cairo. At some point during the occupation, Napoleon learned of the earlier mutinous talk, and confronted Dumas. In his memoirs, Napoleon remembered threatening to shoot Dumas for sedition. Dumas requested leave to return to France, and Napoleon did not oppose it. Napoleon was reported to have said: "I can easily replace him with a brigadier."