Back (apologies for my handwriting!)
The text of the postcard is
You know anything about the mechanics of dog bladders? I take the dog for a walk, she stops 3-6 times to pee! What!? How!? It’s like she’s a hiker rationing water … but the opposite. And does she plan her stops or do they strike her like, “THIS! This spot needs my urine!” Dogs, huh?