The dog is old. I am not sure how old, but dogs don’t really age in years anyway. When we first got her, she would run ahead of me on the trail, then race back as if to make sure I knew the way, then ahead again, before disappearing into the scrub for 10 minutes to chase deer, collect ticks, and coat herself in poison oak, only to emerge 100 yard behind me wondering how I’d had the temerity to get in front of her. If I walked three miles, she ran seven. Her off-trail sorties worried me. I wanted to be the kind of dog owner who let his animal roam. But I’d become attached. I didn’t want to lose her and I didn’t yet know her well enough to know that she would always come back. She was new to us then, a gaunt mongrel, rescued from the mean streets of Madera County, plucked from a high-kill shelter, complete with a right hip full of buckshot, an infected paw, and teats that scraped the ground. There was nothing remotely attractive about her. She barked at strangers, attacked bicyclists,