gone out by themselves?'

'They'd never do such a thing,' I said. 'Why, it's almost quite dark,
and they know mother would be really very angry if they did!'

But Hebe did not seem satisfied.

'The door was shut _very_ softly,' she said.

We were at the drawing-room by this time. There was no light in the two
big rooms, but there were two lamps in the little one where mums sits
when she's alone. No sign of Anne or Serena, however. And no sign of
them in the other rooms either. Alfred brought up a candle, and we
called to them to come out if they were hiding, and said we were really
frightened; but there was no answer.

'They can't be there,' said nurse; 'Miss Anne has far too kind a heart
not to come out, even if they had begun by playing a trick on me. Come
up to the nursery, my dears, and have your tea. I'll go down and speak
to Mr. Barstow. Maybe he can throw some light on it.'

'They must have gone out, nurse,' I said boldly. There was no use not
telling her all we knew.

She turned upon me quite sharply.

'_Gone out_, Master Jack? Nonsense, Miss Anne is far too good and
obedient to do such a wild thing, knowing how it would displease your
dear mamma too.'

But Maud, whom we met on the staircase, suddenly thought of an
explanation of the mystery.

'Come in here,' she said, pulling us all three into the nursery and
closing the door. 'Listen, I do believe I know where they've gone. It's
about the diamond brooch. I believe Anne's gone to those children's
house where they've found a brooch that might be it.'

Hebe and I jumped.

'I believe you're right, Maud,' I said.

'How stupid of us not to have thought of it!' exclaimed Hebe.

But nurse, of course, only stared.

Then we explained to her what Maud meant. Even then she could scarcely
believe Anne had really done such a thing.

'It would have been so much better to wait till your mamma came in,' she
said. 'Alfred could have been sent with a note in a minute.'

'Anne didn't want mother to know about it. At least, I said to her it
would be a pity to raise mother's hopes, and it was all nicely settled
that Flossy Barry was to find out and ask her mother to write if it
seemed possible it _was_ our diamond thing,' I said. 'It is all Anne's
impatience, and you see, nurse, she knew she shouldn't have gone alone
with Serry, or she wouldn't have crept out that way without telling any
one.'

'I don't know how they can have gone to those people's house,' s