Wouldn't it ?" "I s'pose so," said Tilda doubtfully.
"But a boat going up will want a lock full, and that water too.

And that's why an empty boat going downhill takes more water than a loaded one, and less going up." To Tilda the puzzle remained a puzzle.

"It _sounds_ all right," she allowed.

"But what makes you so clever about boats ?" "I've _got_ to know about them.

Else how shall we ever find the Island ?" She thought for half a minute.
"You're sure about that Island ?" she asked, a trifle anxiously.
Arthur Miles turned to her with a confident smile.
"Of course I'm sure." "Well, we'll arsk about it when we get to Stratford-on-Avon." She was about to say more, but checked herself at sight of a barge coming down the canal--slowly, and as yet so far away that the tramp of the tow-horse's hoofs on the path was scarcely audible.