Final answer:
Dramatic irony is used on page 19 of the text.
Step-by-step explanation:
Dramatic irony is a literary device used in storytelling where the audience or reader knows something that the characters do not. On page 19, there is an example of dramatic irony in the form of Twain's description of the dangers multiplying and the peril he imagines. This creates tension and suspense for the reader, as they are aware of the impending danger but the characters are not.