The use of the vernacular in literature is a technique that is particularly effective when a story is written, as this one is, in the voice of a storyteller—that is, somebody who is relating the events of the story to a listening audience. Use of the vernacular is when the author introduces features of language which are more akin to what would be used in everyday speech, without the formality typically found in the written word. In this story, we can see examples of this throughout. The beginning of sentences with a pensive, "Why, if . . ." and the use of phrases such as "uncommon lucky," where technically the adverbial uncommonly should have been used, are just two examples. We also see tense-switching—when the speaker relates what others have said, he uses the present-tense "says" rather than "said."

Why does Twain do this? Well, it certainly adds an immediacy to the story. If we can read a text and feel as if we are listening to the narrator tell the story directly to us, it gives the story a naturalistic feeling and puts us in the position of the avidly listening audience. The story seems more rustic and realistic, as if it could really have happened and become an anecdote rather than something invented by a writer.

You have identified one of the hallmarks of Twain's narrative style - his use of vernacular, or common speak. Twain sought to capture the voices of the people he wrote about, so instead of writing in "proper" English he transcribed literally how people spoke, capturing the way they pronounced words just as much as the slang and idioms they used. Given this definition, it is easy to find many examples of vernacular in Simon Wheeler's narrative. Consider the following: "sorter discouraged-like", "cal'klated to edercate him," and "ketched." Such examples of vernacular help the reader imagine the characters, and in particular the sound of their voice, as well as the setting, and add comedy to the tale by vividly bringing the story to life for us.