O
- Obelisks. (2)
- Oberlin College--Buildings. (5)
- Oberlin College--People. (2)
- Occupations. (1)
- Ocean Park (Santa Monica, Calif.) (1)
- Offices. (3)
- Official residences. (1)
- Ohio Northern University--Buildings. (1)
- Ohio State University--People. (1)
- Ohio State University--Sports. (1)
- Ohio University--People. (1)
- Oil wells. (91)
- Olympic Games--(10th :--1932 :--Los Angeles, Calif.)--People (1)
- Olympic Games--(10th :--1932 :--Los Angeles, Calif.)--Rites & ceremonies (4)
- Open-air theaters. (5)
- Open-air theatrical productions. (1)
- Opera houses. (2)
- Orange orchards. (1)
- Orchards. (9)
- Orchestras. (4)
- Ordnance industry. (1)
- Ore industry. (1)
- Organizations' facilities. (3)
- Organizations. (51)
- Orphanages. (5)
- Orphans. (1)
- Ostriches. (4)
- Outdoor religious services. (1)