Final answer:
Mark Twain employs imagery, characterized by vivid details and hyperbole, in the excerpt from his autobiographical narrative to captivate readers and enhance the narrative's impact.
Step-by-step explanation:
The tool Mark Twain uses in the excerpt from his autobiographical narrative to make it interesting is imagery. This is evident through the vivid details and sensory images he utilizes to engage readers' emotions and create a sense of presence in the scene. Twain's description, such as the electric suddenness of his surprise where he lit in the middle of the floor, brings the narrative to life by appealing to the readers' visual senses, aiding them in imagining the action unfolding. Moreover, by noting the vivid details and hyperbole in his writing, we see how Twain uniquely captures and exaggerates the feelings of panic and surprise to emphasize the intensity of the situation.