Gertrude Atherton. The Avalanche: A Mystery Story (1919) 229 pp.
The mystery in this story is more genealogical than criminal. In San Francisco, in the years immediately following the 1906 earthquake, Price Ruyler has firmly established himself in business and society. He is married to a beautiful young French woman—who was actually born in San Francisco—named Hélène Delano. After he chances to overhear an exchange between his mother-in-law and a man known to have made his living as a pimp and a gambler before the earthquake and fire, he begins to suspect that his wife’s past might not be as innocent as he was led to believe. He hires a private detective named Jake Spaulding to investigate and uncovers a plot involving blackmail and betrayal.
Baird & Greenwood 99; Herron; Hubin