Lifted

A man lifted a pothole cover and called into the darkness. "Are ye all right there lads?" Nothing. "I said are ye all right in there?"
"Piss off!" came out of the darkness. "Yeah, piss off!" voiced another voice, followed by a whole chorus all affirming the same impolite directive.
"All right, all right, I was only checking. So I'll put the lid back on, will I?" Silence. "I could leave it off if ye like." The silence tensed. "I'll put it back so." And he did.
"What a fool!" he'd have heard if he could have, but of course with the lid back on he couldn't."