Names
- Hazen S. Pingree1
- Henry Morgenthau, Sr.1
- Herbert May1
- Hillwood1
- Hillwood (Washington, D.C.)1
- Hobart and William Smith Colleges1
- Holden, Ebenezer G. D., 1845-1912.1
- Hopkins, Enos, 1821-1896.1
- Hopkins, Samuel W., 1845-1
- Hoxie, R. Gordon1
- Humphrey, Hubert H.1
- Hutton, Edward Francis, 1877-1962.1
- Innes, William Powers, 1826-1893.1
- International Association of Bridge and Structural Iron Workers.1
- International Club of Washington, D.C.1
- International Union, United Automobile, Aircraft and Agricultural Implement Workers of America.1
- Iron League of New Jersey.1
- Iron League of New York.1
- Iron League of Pennsylvania.1
- James G. Keenan1