What was discover in shaanxi, china, in 1974?

Answerminuet;

Maybe because it was so unique, a form of art, and they could easily store things in it and no one had ever done that before. i’m not sure but that’s what i think : )

The theme of social protest remained a consistent focus for jacob lawrence throughout his career. in the 1960s lawrence was inspired by news reports and photographs, including images of segregated lunch counter sit-ins and stories of the   freedom riders in the civil rights movement. from the 1970s onward, lawrence's work focused less explicitly on contemporary social issues.