How does the use of authentic dialect add to "The Celebrated Jumping Frog of Calaveras County"?
By using authentic dialect, Twain adds to the story's sense of realism. He creates both an authentic setting and an authentic set of characters. Take the setting, for example. The story takes place in Angel's Camp in California in the mid-nineteenth century. As such, the dialect of people here would be very different to the likes of the narrator. By using the proper, local dialect, Twain makes the setting believable for the reader by immersing us in this world.
Similarly, Twain uses authentic dialect in his characterization of Simon Wheeler who tells the tale to the narrator. You'll notice, for example, that Wheeler uses words like "feller" instead of fellow. By writing his dialogue in this manner, Twain makes him believable for the reader, adding a sense of authenticity to his characterization.
In addition, Twain creates a contrast between the dialogue of the narrator and of Simon Wheeler. The narrator, for instance, uses American dialect that the reader would be more familiar with. By ensuring this level of accuracy, Twain creates a contrast between the worlds of the West and the East, which is, again, more authentic and believable.
Humorists such as Mark Twain make use of exaggertion. Certain exaggerated details and incidents are described by a storyteller in a very serious tone, a tone which makes the story even funnier because the reader gets the impression that the teller is unaware of the ridiculousness of what he is describing (i.e. satire).
The regional dialect is an important element of Twain's humor and use of the ridiculous. These dialects capture the local color and make the characters more interesting and amusing. Simon Wheeler makes for such an interesting character, and his use of unexpected words adds much to the humor of the story. For example, Simon relates, " This-yer Smiley had a mare--the boys called her the fifteen-minute nag...." Such colorful language creates humorous images in the mind of the reader.
Many times, like in Mark Twain's work, authors use regional dialect and even phonetic spelling to add to the authenticity of a piece and its overall impact. Authors purposely choose their setting and characters to reflect and emphasize certain themes, symbols, allusions, metaphors, etc. Think about the novel/film "The Help." The setting is 1950s Jackson, Mississippi, at the cusp of the Civil Rights movement. The characters are upper-middle-class white women and lower-class black "help." It would be very difficult to understand the nuances and racism of this culture, along with the emotion and power of characters like Minnie, if the author hadn't used regional dialects!