about a friend of
ours;' and he told them about the robbery of the post-office and Neil's
flight, while the boys listened with wide-open mouths, throwing
themselves about and uttering exclamations of interest.

'You say that you are quite sure he couldn't have taken the letters?'
asked Harry, drawing himself into an upright position on the heather.

'Perfectly certain,' replied Allan. 'He would no more have done it
than you or I. No one who knows him would believe such a thing of
Neil.'

'Oh!' interposed Tricksy, in a shocked tone, 'I think Dr. MacGregor
believed it.'

Hamish became very red and Marjorie's lips tightened.

'And he's so awfully, awfully jolly,' pursued Harry.

'One of the very jolliest people we know,' answered Marjorie. 'Father
doesn't really believe it of him. He did everything for us, and was up
to all kinds of inventions. We don't seem to have any fun at all
without him.'

'It's a most extraordinary story,' said Harry, jerking himself into a
fresh attitude; and both the new boys sat and pondered.

'What do you say to letting them both join the Compact?' suggested
Reggie.

Marjorie's eyes said yes; and Hamish, whom Allan consulted with a look,
gave a nod.

'What's that; a Compact?' inquired Harry eagerly.

'It's an agreement that we've all made,' said Allan, 'that we'll back
Neil up, and show that he didn't commit the robbery.'

'Hooray, what fun,' said Harry; 'I'm game.'

'You might let Gerald join too,' cried Tricksy from where she sat
beside her new friend; 'he's quite the right sort, and he only wants to
learn a thing or two to be equal to any of us.'

Gerald wriggled, and blushed to the roots of his golden hair.

'Well, then, you must do all you can to help us,' said Allan, 'and see
whether you can find out who really did it.'

'All right,' said Harry; 'I'll help you to catch the thief.'

'And you must sign an agreement like the rest of us, and you can each
have a copy to carry about with you always, as we do. See, this is the
principal copy, that I have to take care of.'

'You can write it out now, with Allan's new fountain pen,' cried
Tricksy; 'this flat stone will do for a desk, and I've got some pieces
of paper that I've been carrying in my pocket in case we might find any
new people to join our Compact;' and she produced with great gravity
some crumpled sheets of note-paper, much soiled at the edges.

'All right,' said Allan, 'this is the agreement; "We hereby