They were sure of catching them; for this was not the first time the parties had measured speed.

In the open ground they had gained visibly on the three this morning, and now, at last, it was a fair race again, to be settled by speed alone.

A hundred yards were covered in no time.

Yet still there remained these ten yards between the pursuers and the pursued.
This increase of speed since the morning puzzled Dierich Brower.

The reason was this.