John Muir was born in Dunbar Scotland, in 1838 but grew up in Wisconsin.He walked from the Ohio River a thousand miles to the Gulf of Mexico, where he planned to continue south to explore the jungles of the Amazone. However, about with malaria turned his sights west to California, where he arrived in 1858, immediately falling in love with the land.

   Over the next decade Muir became well known as a Sierra Nevada mountaineer, explore and naturalist. Later, Muir built another more significant career upon his first. He became the nation's foremost conservationist. Yosemite National Park was established in 1890 essentialy because of Muir's recommendations.

   Two years later he helped the Sierra Club, which originally limited it's conservation activities to preserving the forest and other natural features of the Sierra Nevada Mountains" before it branched out in recent years to tackle global issues.

    In 1903, Muir lured Theodore Roosevelt away from his presidential entourage to spend three nights in Yosemite. Later, the President remarked to his party that the time he spent talking conservation with Muir was "the greatest day of my life”. His administration were to make the most sweeping conservation effort the nation's history.

What is the communicative purpose of this passage?