In 1913 Markov hand-counted 20,000 letters of Pushkin, marking each as vowel or consonant, to show the law of large numbers holds for dependent events.
When the chain is played back, the output simulates the original text's consonant-to-vowel cadence.
vowel consonant
Dashed line = what you'd expect if each letter were drawn independently. The gap is the dependence.
Inspired by the artwork in First Links in the Markov Chain by Brian Hayes.