Following a night out with a few friends, a man brought them back to show off his new flat. After the grand tour, the visitors were rather perplexed by the large gong taking pride of place in the lounge.
"What's that big brass gong for?" one of the guests asked.

"Why, that's my Speaking Clock" the man replied.

"How does it work?"

"I'll show you", the man said, giving the gong an ear-shattering blow with an unpadded hammer.

Suddenly, a voice from the other side of the wall screamed, "For Christ sake, you idiot, it's twenty to two in the morning!!"