Maybe it was but the dipping wing of a gull.
But it was not that.

Presently I also saw the speck he meant, and it did not disappear again.

It was the head of a square, brown sail, the ship herself to which it belonged being hull down, but holding the same course as ourselves, or thereabouts, so far as one could judge as yet.

And before long a second hove up from astern the first.
"They are running a bit freer than we," Bertric said.

"They have a shift of wind astern of them, whereby they are overhauling us." "Two brown-sailed ships," said I."They mind one too much of Heidrek to be pleasant, else one might welcome the coming of any honest Norsemen who would help us to do the right." "Wait, and I will tell you," answered Bertric somewhat grimly.