Twice she felt the logs of a rude bridge under the wheels as they crossed some stream.

They were winding their way up the valley of a stream, into a higher country?
Yes.

As they climbed now, she could catch the scent of the forest as the wind changed from time to time.

The profanity of her captor grew as the difficulty of the trail increased.

They were climbing at a gradient as steep as the laboring car could negotiate.
At last, after interminable time, they seemed to strike a sandier soil, more level country--indeed, the trail was following the contour of a high sandy ridge among the pines.
On ahead she heard a shout.