After discovering a distinctive smell of nutmeg at several crime scenes, Sherlock employs The Nose to smell the scene of a murder in a park band shell. Holmes indicates that The Nose has a better sense of smell than his own. Watson asks what The Nose's name is, but Sherlock doesn't know. The Nose is able to detect not only the nutmeg but also bleach, something metallic and sodium hydroxide. Holmes is able to deduce that the murder scenes are linked by a common cleaner, not a common killer. ("The Adventure of the Nutmeg Concoction")
While investigating cigarette smuggling, Watson detects an odd smell in some samples. She calls The Nose to help as Sherlock is busy dealing with his father Morland. Holmes arrives at The Brownstone to find The Nose smelling cigarette samples. Holmes is put off that Watson didn't use his nose and it's revealed that Holmes harbors resentment towards The Nose who critisized Holmes' monograph on ash. The Nose then scolds Watson and Holmes for talking while he is smelling. He then reports various smells he's detected in the cigarettes, the most important of which is hops grown in Oregon. This leads Watson to realize that the cigarettes are being smuggled into a craft brewery. ("You've Come a Long Way, Baby")
Tobacco is the one area of olfaction we've agreed to disagree.