"I feel sure that the girl referred to in the old letter is my sister; but how can I identify her, in case I meet her, until I know what sort of a mark she has, and where it is?"
"You can't!" declared Will, positively.
"And that makes it all the more tantalizing," went on Mr. Blackford. "They even—that firm I spoke of—they even had located the part of the country where it might be possible my sister was, and now to have it fail this way——"
"Where did they say she might be?" asked Amy.
"Somewhere up in Canada. But it is rather vague. If only that piece was not torn off the edge of the letter!"
"Can't you find it somewhere?" asked Mollie. "Maybe in forwarding it the people you hired tore it by accident."
"I thought of that, so I telephoned as soon as I got this letter, asking where the missing piece was. I got word back that they knew nothing about it."
There was silence for a moment, while they all looked at the mutilated document Mr. Blackford held up. It showed a tear across one corner, a tear that disposed of the most vital piece of information contained on the whole paper.
"That's too bad," spoke Amy, sympathetically.
"Yes," agreed Mollie, as she put back a stray and rebellious lock of hair, "it spoils all your plans, I suppose, Mr. Blackford."