Upon entering the room, Sherlock Holmes notices that no one heard the man. He saw the newspapers, and believed that his mouth had been cover. He also noticed that someone must have turned the lights off therefore, the victim wouldn't have seen his death coming. Sherlock Holmes noticed that there was no weapon, but he knew that something sharp wounded the man on his chest. He saw a metal water bottle. He wonder what could be hidden in there that was sharp and leave no trace. So, he thought of a solid piece of ice which melted after the man was wounded. He put all the pieces together and arrested all the suspects.