What is some irony in "The invalids story" by mark twain?

In mark twains piece of literature, the invalids story, irony is repeatedly used

In mark twains piece of literature, the invalids story, irony is repeatedly used

- they don't want to get sick from the smell, but they eventually get sick from the coldness

- dramatic irony; the responder knows that a bag of cheese was left on the box, but the two men in the train don't know this