- Nellist, J. F. (John F.)1
- New York State Geological Survey1
- Newberry, J. S. (John Strong), 1822-18921
- Newberry, J. S. (John Strong), 1822-1892, geologist.1
- Norton, S. F. (Seymour Francis), 1843?-19121
- Nozaki, Sabun, 1858-19351
- O'Hare, Daniel1
- O.W. Gray & Son1
- Ochikochi, Dōin, 17th cent.1
- Odagiri, Takeo.1
- Ode, H. (Henri)1
- Ohman Map Co.1
- Ojea, Ferdinand.1
- Old Corner Bookstore (Springfield, Mass.)1
- Olmsted Brothers1
- Ontario. Department of Crown Lands1
- Oregon Railway and Navigation Company1
- Osborn, Chase S. (Chase Salmon), 1860-19491
- Ottawa. Geological Survey Department, surveyor.1
- Overton, Henry, 1675 or 1676-1751.1