REMOVE

1. shadows
2. neckties
3. pillars
4. 1969

WHAT

1. banks (landforms) (1)
2. black-and-white film (2)
3. construction sites (1)
4. cranes (equipment) (1)
5. dams (hydraulic structure … (1)
6. exterior views (1)
7. fields (land) (2)
8. freight cars (2)
9. Grand Coulee Dam (dam) (1)
10. landscapes (representatio … (1)
11. men (male humans) (3)
12. plants (2)
13. railroads (2)
14. rails (transit system ele … (2)
15. rock (3)
16. scaffolds (1)
17. silver gelatin (1)
18. sky (3)
19. soil (2)
20. tools (3)
21. towers (single built work … (1)
22. trains (vehicle groupings … (2)
23. trees (2)
24. trucks (3)
25. utility poles (2)
26. Visual Works (hierarchy n … (3)
27. wood products (1)
28. workers (1)
29. wrecks (sites) (2)

Less

WHERE

1. New Windsor, Maryland (2)
2. Grand Coulee, Washington (1)

WHO

1. Clyfford Still; Still, Cl … (3)
2. Still, Clyfford (3)
3. Campbell, Sandra L. Still (2)
4. Sandra L. Still Campbell; … (2)

More 

WHEN

1. 1936 (1)
2. 1937 (1)
3. circa 1936 to 1937 (1)