No Gods. No Masters.
Another way to look at this is:
men place animal famous for biting and tearing things apart, a literal "terrier" in front of expensive machine and are shocked when the obvious occurs.
@futurebird It's hard to be sure, but they don't actually seem surprised. It looks as though the guy on the right lets go of the dog once it's already staining to get at the phonograph horn. The one on the left doesn't exactly rush to stop it. Given that it was being filmed, I wonder if they simply let this happen for the camera?

@DamonWakes @futurebird

I agree. I watched a longer version on YouTube (it's called Nipper Runs Amok, although this isn't the original Nipper, who was dead by then), and they're smiling and laughing through the whole thing.