Maybe because it is skin-searingly hot here in Houston, but when I look at these pictures, I think, how did they stand it? All the people, all the clothes, no a/c.

I think people must have been made of much tougher stuff back then.

Maybe they were acclimated, as it gradually warmed up, they got used to it. When I was a kid I slept in the attic, with no air conditioning, just a big window fan in the north window sucking air out of the whole house. When my uncle from Michigan would visit in August (to Missouri) he couldn't understand how we could stand the heat--he was burning up. Of course Michigan in the summertime doesn't have the heat & humidity level of MO. (our sauna season)--so of course he was burning up.