Final answer:
Mr. Mayherne's nervous habit is not specifically mentioned in the provided passages. Instead, characters like Nippers and McTeague are highlighted with their own nervous behaviors such as irritability and restlessness.
Step-by-step explanation:
The passages provided indicate that the character Mr. Mayherne does not have a specifically mentioned nervous habit. Instead, various characters from different literary works are described with their own unique nervous habits. For example, Nippers from the passage shows an irritable disposition and is prone to impatient behaviors in the morning, such as moving his desk in frustration.
Another character exhibits a nervous agitation demonstrated by attempts to overcome a habitual trepidancy. Mrs. Peters in a different passage is depicted as nervous and fidgety, while McTeague struggles with restlessness at night due to emotional turmoil. These examples illustrate that nervous habits can manifest in a variety of behaviors in different characters across literature.
Mr. Mayherne's nervous habit was shown through his restless and agitated behavior. He would sometimes impatiently rise from his seat, spread his arms wide apart, and move his desk with a grinding motion on the floor. This habit was likely due to an irritable and brandy-like disposition that he was born with.