But I could make out nothing.

The sea was rising a little, but that was of course as the breeze freshened steadily.

There was no sign of change or of heavier weather to come, and no dark line along the eastward sea warned me of a coming squall.

Yet Bertric still turned from the helm and looked astern.
"What is it ?" asked Gerda.

"Go and see, and call me if it is aught." So I went aft again, and stood beside Bertric, asking him what had caught his eye.
"I cannot say for certain," he said; "but it seemed to me that for a moment somewhat like a sail lifted on the sea's rim off yonder." He pointed off the port quarter, and turned to the helm again, leaving me to see if I could catch sight of what he had seen.