Two guys are hunting in the woods...

One of them spots a hole in the ground that looks unusually deep. He picks up a rock and throws it in the hole, and never hears it hit the bottom. "Try something heavier?", the other man suggests. They find a rusty old anvil nearby, pick it up and throw it down the hole. Five seconds later a goat comes speeding toward the hole and falls in. "What the hell was that?", one of the men say. Just then another man runs up and says "Please, have you seen my goat anywhere?!". "Yes", they reply,"We just saw him run this way and jump into this hole!" The man says, "That's impossible I had him tied to an anvil."