Smoking cigars helped a famous author write... Mark Twain

Mark Twain — master of epistolary snark, unsuspected poet, cheeky adviser of little girls — followed a simple but rigorous routine: 

Mark Twain [ Samuel Clements ]

He would go to the study in the morning after a hearty breakfast and stay there until dinner at about 5:00. Since he skipped lunch, and since his family would not venture near the study — they would blow a horn if they needed him — he could usually work uninterruptedly for several hours. … After dinner, Twain would read his day’s work to the assembled family. He liked to have an audience, and his evening performances almost always won their approval. On Sundays, Twain skipped work to relax with his wife and children, read, and daydream in some shady spot on the farm. Whether or not he was working, he smoked cigars constantly.