As Latour, nearing his death, considers whether to return to Auvergne or stay in New Mexico, Cather employs personification to imbue Santa Fé's air and land with human-like qualities:
He had noticed that this peculiar quality in the air of new countries vanished after they were tamed by man and made to bear harvests […] The moisture of plowed land, the heaviness of labor and growth and grain-bearing, utterly destroyed it; one could breathe that only on the bright edges of the world, on the great grass plains or the sage-brush desert. [...] Something soft and wild and free, something that whispered to the ear on the pillow, lightened the heart, softly, softly picked the lock, slid the bolts, and released the prison spirit of man into the wind, into the blue and gold, into the morning, into the morning!
The air of New Mexico in this passage becomes like a living, “whispering” being with its own agency. It has the capacity to “unlock” things, pointing to the sense of liberation and release Latour feels in the “new countries” he has spent most of his adult life in. He can only be joyfully released "into the morning" in these relatively "untamed" lands.
The land of Europe is personified in the opposite way here, as a wild entity that has been subdued by man. It is portrayed as a living force that has been tamed and crushed, made to bear harvests through human labor and cultivation. Compared to the “wildness” of New Mexico, Latour thinks of humanity as being “captive” within the tamed and cultivated land. His yearning for “something soft and wild and free” prevents him from wanting to leave. The air in New Mexico “picks the lock” of civilization and makes him feel alive and renewed.