Jennifer stared at the new-moon stone hopefully, but all it did was
dangle there in the air. 'When does it start to do something?" she
whispered.
"Don't ask me," said Moffat and he grinned.
'Well, I can't ask the stone, can I?" said Jennifer.
The new-moon stone suddenly began to swing up and down.
"You can!" said Moffat with satisfaction. "You see?"
"See what?"
"It's doing it," whispered Moffat.
"Oh," said Jennifer. "Is that all it does?"
The new-moon stone switched its direction and started to swing back
and forth instead. Moffat laughed.
"It likes you!" he said. "Here, take the chain and try
it yourself. It works even better if you hold it."
He handed over the chain. Jennifer was still puzzled. "I still
don't see what it is exactly," she whispered.
"It's a pendulum," explained Moffat."Rather an odd and
old-fangled contraption, but it works extremely well."
"But how does it work?" asked Jennifer.
"Do you know how a compass works?" asked Moffat.
"Sure," said Jennifer. "It always points to the north."
"A pendulum works by pointing too, but it points to the truth instead,"
said Moffat. "It swings one way for yes, another for no. All you
have to do is ask it."
"What can I ask?"
"Whatever you want, so long as the answer is yes or no. Yes or
no, that's all it can say but that's saying a lot if you ask the right question,"
said Moffat. He looked down at the pendulum and laughed. "See for yourself,
what I'm saying is true; the new-moon stone was listening to me and it definitely
agrees. It's swinging up and down and that means yes."
He was right about that, the new-moon stone was swinging up and down,
up and away and then back again.
"It looks like it's nodding its head," said Jennifer.
"That's it, that's yes," said Moffat. "Now tell it something
else and make it say no, go on, go ahead!"
"Does my great-grandfather have eyes like pies and a nose like
a hose and a chin like a pumpkin?" she said.
The new-moon stone changed directions and began to swing to and fro,
back and forth in front of her chest.