Our transcription: Some of this wind-blown dust can be a blessing. The soil of the Midwestern United States owes much of its fertility to what geologists call "loess." Loess is made up of fine particles of silt and clay that have drifted in over the millennia from barren lands uncovered by melting Pleistocene ice. In Eastern China deposits of loess have reached remarkable proportions, hundreds of meters thick. From time immemorial the Chinese have carved cave dwellings out of this soft, but surprisingly cohesive, material.
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