A lot of wealthy Ohioans had summer cottages up on Put In Bay, and there wasn't any AC anywhere on the entire island. They were all used to it even though it was sweltering and humid as Hell. They'd make fun of their guests when we'd come up for a weekend and be just dying of the heat the entire time.
Vermont was the same way, only there it was only hot in July. So they'd just sweat it out for a month, and the that would be the end of it.