After arriving in Cuba, the extreme heat and constant mosquitos were a major problem. O'Reilly also claimed the extremely poor quality rations were "a slimy, ill-smelling mess, disgusting in appearance and fatal in effect." He first witnessed action in The Battle of El Caney. The battle was a failure for the American side and O'Reilly described the chaos the battle degenerated into. Shelling from Spanish artillery's had disoriented him, and how the heat and lack of water lead to some of his comrades fighting each other over canteens in the middle of the battle. He jumped into a trench where a Spanish soldier raised his gun on him, only to be saved at the last second when a Black American soldier killed him at the last second.