British scientist James Smithson died in 1829 and left most of his wealth to his nephew; when the nephew died childless in 1835, the estate passed "to the United States of America, to found at Washington, under the name of the Smithsonian Institution, an Establishment for the increase & diffusion of knowledge among men", in accordance with Smithson's will. Congress officially accepted the legacy bequeathed to the nation, and pledged the faith of the United States to the charitable trust on July 1, 1836. The American diplomat Richard Rush was dispatched to England by President Andrew Jackson to collect the bequest. Rush returned in August 1838 with 105 sacks containing 104,960 gold sovereigns.

Years of Congressional haggling then ensued over how to interpret Smithson's vague mandate "for the increase and diffusion of knowledge." Unfortunately the money was invested by the US Treasury in bonds issued by the state of Arkansas which soon defaulted. After heated debate, Massachusetts Representative (and ex-President) John Quincy Adams persuaded Congress to restore the lost funds with interest and convinced his colleagues to preserve it for an institution of science and learning. Finally, on August 10, 1846, President James K. Polk signed the legislation that established the Smithsonian Institution as a trust instrumentality of the United States, to be administered by a Board of Regents and a Secretary of the Smithsonian.

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