Smithsonian Institution is the largest museum complex and research organization in the world and is headquartered in Washington, D.C. Composed of 16 museums and the National Zoo in Washington, D.C., and two museums in New York City, the Smithsonian's exhibitions offer visitors a glimpse into its collection that numbers more than 142 million objects. The museums are separated into fields including modern and contemporary art, African American history and culture, natural history, Asian art and a portrait gallery. In 1826, James Smithson, a British scientist, drew up his last will and testament, naming his nephew as beneficiary. Smithson stipulated that, should the nephew die without heirs (as he would in 1835), the estate should go to the United States of America, to found at Washington, under the name of the Smithsonian Institution, an establishment for the increase and diffusion of knowledge among men.