Hard economic times and social conflict have always offered a rich source of material for artists and writers.A painter's colors can show the drying of dreams or the flight of the human spirit.A musician can express the tensions and uncertainty of a people in struggle.The pressures of hard times can be the force to lift a writer's imagination to new heights.So it was during the nineteen-thirties in the United States.The severe economic crisis -- the Great Depression -- created an atmosphere for artistic imagination and creative expression.The common feeling of struggle also led millions of Americans to look together to films, radio, and other new art forms for relief from their day-to-day cares.This week in our series, we tell about American arts and popular culture during the nineteen-thirties.