Dust Flower, The by Basil King (1859 - 1928)

Rashleigh Allerton, a wealthy New Yorker, quarrels with his well-to-do fiancée Barbara and impetuously says that he will marry instead the first person he meets. The book follows the result of this absurd promise, with consequences that neither of them (nor Rashleigh’s faithful elderly man-servant Steptoe) expect. - Summary by Simon Evers