When next Jack came to the surface, he found himself in what seemed a long, narrow gallery, nearly filled with water; a low, vaulted roof just above him, and an opening at each end through which shone the light of the sky. Drops from the clammy and dripping stones fell with slow, echoing plashes in the cavernous gloom, reminding him that he was under the canal; that the great, winding, watery thoroughfare, which he had travelled many a summer, and through which the lazy boats moved, was now over his head.