Zane Grey 
Captives of the Desert [EPUB ebook] 

When John Curry, galloping across the desert to save the life of an Indian child, was thrown from his horse and badly injured, he was rescued by a woman whose husband became his deadly enemy. For Wilbur Newton was both jealous and afraid. He was jealous of the love of his beautiful and lonely wife, who seemed each day more powerfully attracted to the dashing Curry.