Wednesday morning as my daughter and I drove to school we saw a black dog loping along the main road near our home. A big intact male, its coat the color of carbon, with the long legs of a hound and the jawline of a pit fighter. A free dog, without collar. Walking slowly, almost lackadaisically, the same way the urban coyotes often are if you encounter them at the end of a long night’s prowl. One of those specters of the invisible city not really meant for you to see.