February 5, 1865. "Abraham Lincoln, seated, holding spectacles and a pencil." Glass transparency; photograph by Alexander Gardner. View full size.

Washington, 1918. "Navy Dept. stores." Everything here seems to be addressed to "Hon. Franklin D. Roosevelt, Asst. Sec. of Navy, c/o Naval Observatory." Who can hazard a guess as to what might be in these boxes? View full size.

1917. Washington, D.C. "Congressional baseball game. President and Mrs. Wilson." Harris & Ewing Collection glass negative. View full size.

March 18, 1919. "Caruso and Muzio." Famed Italian tenor Enrico Caruso with the soprano Claudia Muzio in New York during his 15th year with the Metropolitan Opera and two years before his death. G.G. Bain Collection. View full size.

June 27, 1929. "President and Mrs. Hoover greeting their guests at White House reception for veterans." National Photo Company glass negative. View full size.

May 21, 1925. "White House garden party for wounded veterans. President and Mrs. Coolidge greeting guests." National Photo glass negative. View full size.

December 22, 1924. "J.E. Hoover, Bureau of Investigation, Department of Justice." A young J. Edgar Hoover, age 29, director of the government agency that we know today as the FBI. National Photo glass negative. View full size.

August 1956. "Attendees at the Republican National Convention, San Francisco, California." They liked Ike, and Richard Nixon too. Photograph by Thomas J. O'Halloran, U.S. News & World Report. View full size.

July 24, 1929. "Norma Shearer (Mrs. Irving Thalberg)." The Oscar-winning actress at the White House. National Photo Co. glass negative. View full size.

October 4, 1924. "Sisler, Ruth, Cobb." George Sisler, Babe Ruth and Ty Cobb at the first game of the 1924 World Series at Griffith Stadium in Washington, D.C. National Photo Company Collection glass negative. View full size.

1862. The Peninsula, Virginia. "Lt. George A. Custer with dog." Photographs from the main Eastern theater of war, the Peninsular Campaign, May-August 1862. Wet plate glass negative, photographer unknown. View full size.

April 24, 1973. "Interview with Lt. Commander John S. McCain, Vietnam prisoner of war." Medium format negative by Thomas J. O'Halloran. View full size.

February 1944. The folk singer Pete Seeger entertaining Eleanor Roosevelt, honored guest at a Valentine's Day party to mark the opening of the United Federal Labor Canteen in Washington. View full size. Medium-format safety negative by Joseph Horne for the Office of War Information.

"Tom Thumb, full-length portrait, facing front, standing on table." Half-plate daguerreotype c. 1850-55 from the studio of Mathew Brady. View full size.

"Major General George Armstrong Custer, officer of the Federal Army" circa 1865. Wet plate glass negative, studio of Mathew Brady. View full size.