The horses trotted.

And the exercise soon warmed Helen, until she was fairly comfortable except in her fingers.

In mind, however, she grew more miserable as she more fully realized her situation.

The night now became so dark that, although the head of her horse was alongside the flank of Bo's, she could scarcely see Bo.

From time to time Helen's anxious query brought from her sister the answer that she was all right.
Helen had not ridden a horse for more than a year, and for several years she had not ridden with any regularity.