I was right under the air conditioner, which was set to 61 degrees Farenheit, and I got colder as the evening went on, until, during the Q&A, ladymondegreen asked if I were all right. I pointed at the air conditioner, and she understood. mneme now understood why I was trying to burrow into my jacket and under my arm, and put his trenchcoat around me, which improved matters.
I figured the temperature had to be down that low to make sure the packed room was kept comfortable. Alas, this did not actually happen. It never occurred to me to wonder why mnemex wasn't shivering, even though he was right next to me, and I'm not a great heat shield.
It turned out that the spot where I was sitting was the only one enjoying the benefits of the air conditioner. Everyone else was sweltering, which is why ladymondegreen was so concerned, figuring I might be getting a fever.