REMOVE

1. service stations
2. plants
3. sky
4. machinery
5. black-and-white film

WHAT

1. buildings (structures) (1)
2. exterior views (1)
3. fences (1)
4. ladders (1)
5. platforms (general) (1)
6. railroads (1)
7. rails (transit system ele … (1)
8. signs (declatory or adver … (1)
9. utility poles (1)
10. Visual Works (hierarchy n … (1)

WHEN

1. 1920 (1)
2. 1940 (1)
3. between 1920 - 1940 (1)