"curiosest..."See in text(The Celebrated Jumping Frog of Calaveras County)
“Curiousest” means most curious, another example of Twain’s approximating in writing Wheeler’s spoken language. The remainder of Wheeler’s narrative about Jim Smiley is written in vernacular style, which often adds to the humor in the story.
"the big flume warn't finished..."See in text(The Celebrated Jumping Frog of Calaveras County)
A flume is a artificial waterway sometimes used to transport materials. “Warn’t,” meaning “wasn’t,” is an example of Twain’s vernacular style in the story. “Vernacular” refers to the everyday spoken language of people in a particular locality or of a particular culture or social class. The striking contrast between Simon Wheeler’s speech and the narrator’s contributes to the humorous contrasts between their characters.
"the monotonous narrative which follows this paragraph..."See in text(The Celebrated Jumping Frog of Calaveras County)
The narrator alerts readers that he is about to share the story that Simon Wheeler told him. Wheeler’s “monotonous narrative” will become the story within a story in this frame tale.
"If that was the design, it certainly succeeded.
..."See in text(The Celebrated Jumping Frog of Calaveras County)
Twain’s short story is an example of a frame tale, a narrative that consists of a story within a story. The first story acts as a “frame” within which a second story is told; the second story is often more prominent or important than the first. The unnamed narrator’s story of visiting Simon Wheeler is the frame; Wheeler then tells the narrator a story about Jim Smiley.