March 1939. "Mexican man in front of movie theater. San Antonio, Texas." 35mm negative by Russell Lee for the Farm Security Administration. View full size.

October 1942. "Testing electric wiring at Douglas Aircraft Company. Long Beach, California." View full size. 4x5 Kodachrome transparency by Alfred Palmer.

Chicago, January 1943. "Chicago, Milwaukee, Saint Paul and Pacific 'Hiawatha' about to leave from Union Station." View full size. Photograph by Jack Delano.

Philadelphia, November 1839. "Robert Cornelius, self-portrait facing front, arms crossed. Inscription on backing: The first light-picture ever taken. 1839." One of the first photographs made in the United States, this quarter-plate daguerreotype, taken in the yard of the Cornelius family's lamp-making business in Philadelphia, is said to be the earliest photographic portrait of a person. View full size.

Cincinnati circa 1850s. "Unidentified woman, half length portrait, seated with arm on table." Sixth-plate daguerreotype by James Presley Ball. View full size.

Circa 1844-1860, another portrait sitter from the studio of Mathew Brady, this one with a striking amoeba-shaped chapeau. "Unidentified woman, head and shoulders portrait, facing front. Sixth-plate daguerreotype. Hallmark: Rinhart 31. Scratched on back of plate: 304. Same sitter as in Dag No. 116." View full size.

Circa 1844-1860 daguerreotype from the studio of Mathew Brady. "Unidentified man, head-and-shoulders portrait, facing slightly right." View full size.

1862. On the James River in Virginia. "Effect of Confederate shot on Federal ironclad Galena." Wet plate glass negative by James F. Gibson. View full size.

July 9, 1862. "James River, Virginia. Sailors relaxing on deck of the U.S.S. Monitor." From photographs of the Federal Navy and seaborne expeditions against the Atlantic Coast of the Confederacy, 1861-1865. View full size. Wet plate negative, left half of stereograph pair. Photograph by James F. Gibson.

December 1936. "Mrs. Charles Benning sweeping steps of shack in Shantytown. Spencer, Iowa." Seen earlier here with her baby. View full size. 35mm nitrate negative by Russell Lee for the Resettlement Administration.

1925. Sidney Lust's Leader Theater at 507 Ninth Street NW in Washington, D.C. Now playing: "The Air Mail," starring Douglas Fairbanks Jr., and an "Our Gang" short. National Photo Company glass negative. View full size | Even bigger.

November 1941. Youngstown, Ohio. "Slag runoff from open-hearth furnace. Republic Steel Corporation." View full size. 4x5 Kodachrome transparency by Alfred Palmer for the Office of War Information.

May 1940. "Young migratory agricultural workers singing at the Saturday night dance. Agua Fria migratory labor camp, Arizona." View full size. Medium format negative by Russell Lee for the Farm Security Administration.

December 1936. "Mrs. Charles Benning and baby in their shack home at Shantytown. Spencer, Iowa." View full size. 35mm negative by Russell Lee.

June 1942. Fort Knox, Kentucky. "Infantryman with halftrack. A young soldier sights his Garand rifle like an old-timer. He likes the piece for its fine firing qualities and its rugged, dependable mechanism." 4x5 Kodachrome transparency by Alfred Palmer for the Office of War Information. View full size.