It was Isaac's.
Although the sun had long gone down behind the hills daylight lingered.

It was bright enough for the watchers to recognize Isaac Zane.

He sat high on his horse and in his hand he held the bridle of a pony that was swimming beside him.

The pony bore the slender figure of a girl.

She was bending forward and her hands were twisted in the pony's mane.
By this time the Colonel and Jonathan were standing in the shallow water waiting to grasp the reins and lead the horses up the steep bank.