How Did Ancient Romans Survive Summer Without Air Conditioning?

How Did Ancient Romans Survive Summer Without Air Conditioning? The wall beside your sleeping mat is still warm at midnight. Not the ambient warmth of a summer night — the stored warmth of a building that has been absorbing sun since dawn, and is now, hours after dark, returning everything it collected. You press your palm flat against it. It pushes back. This is your apartment on the third floor of an insula in the Subura district, which is to say the most densely populated neighborhood in the most populated city on earth, and it is July, and you are not sleeping.