REMOVE

1. sky
2. machinery
3. rock
4. houses
5. roads
6. black-and-white film
7. barriers

WHAT

1. Visual Works (hierarchy n … (1)
2. Yaddo (1)
3. artists (visual artists) (1)
4. buildings (structures) (1)

More 

WHERE

1. Yaddo, Saratoga Springs, … (1)

WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. 1934 (1)
2. 1935 (1)
3. ca. 1934-35 (1)