Lone Ranger returns

The Lone Ranger and Tonto ride into town one dusty, dry, Wild West day and proceed to the first saloon, where they tie up their trusty steeds and head in for a snort.
After a while a stranger walks into the bar and asks, “Who owns the white horse tied up outside?”
The Lone Ranger says, “Why, that would be mine. Why do you ask?”
“Because it’s collapsed and looks like it’s dying,” says the stranger.
So the Lone Ranger and Tonto head out to check on Silver.
“He’s probably just suffering from the heat,” says the Lone Ranger. He asks Tonto if he could run around Silver for a while to help keep him cool.
The Lone Ranger returns to the bar and after half an hour another stranger walks in and asks, “Who owns the white horse outside?”
The Lone Ranger says, “That’s mine, what’s the problem this time?”
“Oh, no problem,” says the stranger, “it’s just that you’ve left your injun running.”