Sentence:  It is characteristic of her that she hates trains, that she arrives from a rail-road journey a nervous wreck; but that she can <WSD>ride</WSD> a horse steadily for weeks through the most dangerous western passes. 
Meaning of the word marked with <WSD> tags:  To transport oneself by sitting on and directing a horse, later also a bicycle etc. (from 8th c., transitive usage from 9th c.)