The main conflict in Mark Twain's humorous story is the struggle of the minds of the two men--human minds that Twain was known to have believed dangerous objects--to deal with a horrendous odor.
The conflict in Mark Twain's "The Invalid's Story" derives from the efforts of the narrator/protagonist and the expressman, named Thompson, as they attempt to deal with the horrible smell that they are convinced emanates from the coffin of his "poor departed friend," John B. Hackett, whom the narrator is transporting by express train two hundred miles to his parents' home in Wisconsin. The men try a few different things that fail because they do not realize that it is Limburger cheese that is the cause:
- They break the glass of one of the windows and go to the open window to inhale fresh air periodically.
- When the cold winter air then enters, the men decide to build a fire, but this causes the Limburger cheese to melt and the odor to become more offensive.
- They smoke cigars to disguise the smell.
- They step outside the car to breath fresh air.
- They push the coffin to the end of the express car, but it does not help.
- They use carbolic acid to mask the smell; however, it just creates another offensive odor.
- Thompson sets a bonfire of chicken feathers, dried apples, sulphur, and other items.
- They conclude that the only thing they can do is spend the rest of the trip out on the platform despite the frigid temperatures. In addition, the narrator admits that they know it may mean their deaths from typhoid fever (they do not die, but do become very ill).
All the men's attempts to solve the problem of the smell become futile because they have not identified what the smell is. Nor do they know what is held in the coffin in the first place: guns. The friend's body in a coffin is in another part of the train. Indeed, their minds have worked against them.
We were taken from the platform an hour later, frozen and insensible, at the next station, and I went straight off into a virulent fever, and never knew anything again for three weeks.
The narrator claims this illness has made an old man of him now.
The humor of Twain's story revolves around this conflict because not only are their efforts somewhat ridiculous, but also the smell is not at all from a decaying body. Twain was known for his belief that the human brain could be a dangerous object.