Henri-Laurent de Marigny is a character in Brian Lumley's Titus Crow series — the ally and chronicler of occult investigator Titus Crow, connected to the Clock of Dreams through his family lineage.
In the early short stories the device is sometimes called "de Marigny's clock" because of his father's prior ownership. The coffin-shaped grandfather clock functions as a time-and-dimension-travelling vessel, navigating dreamscapes and alternate realities to combat the forces of the Great Old Ones.