Barzun and Taylor: "Period piece though it is, this neat locked-and-barred-room puzzle retains much freshness and charm." Published in 1891, it seems in fact to be the first classical locked-room mystery. The characters (including rival detectives, long-suffering widow landlady, ambitious labor leader, softhearted freethinker, and sponging aesthete) may be types, but they're not lifeless or wooden; genially satirical humor as well as a deftly turned murder mystery makes this little novel still worth reading.