Psammead altogether.

Then there was a wretched silence. Cyril broke it--

'What shall we do?'

'Go back to the shop and see if they haven't got the other half,'
said the Psammead. 'I'll go to sand till you come back. Cheer
up! Even the bit you've got is SOME good, but it'll be no end of
a bother if you can't find the other.'

So Cyril went to the shop. And the Psammead to sand. And the
other three went to dinner, which was now ready. And old Nurse
was very cross that Cyril was not ready too.

The three were watching at the windows when Cyril returned, and
even before he was near enough for them to see his face there was
something about the slouch of his shoulders and set of his
knickerbockers and the way he dragged his boots along that showed
but too plainly that his errand had been in vain.

'Well?' they all said, hoping against hope on the front-door
step.

'No go,' Cyril answered; 'the man said the thing was perfect. He
said it was a Roman lady's locket, and people shouldn't buy
curios if they didn't know anything about arky--something or
other, and that he never went back on a bargain, because it
wasn't business, and he expected his customers to act the same.
He was simply nasty--that's what he was, and I want my dinner.'