A 1901 series United States ten-dollar bill, a unit of the country's currency. On the obverse it depicts the explorers Meriwether Lewis and William Clark together with an American bison, and on the reverse is an allegorical figure of Columbia between two Roman-styled pillars. This large-size note measured approximately 7+2⁄5 × 3+1⁄8 inches (189 × 79 mm).Banknote: Bureau of Engraving and Printing (image courtesy of the National Numismatic Collection, National Museum of American History)