follow us on twitter at c-span history. and to keep up with the latest -- historys for news. preserves access to films, televisions, radio broadcast that sound recordings. american history visited the packard campus to learn about the earliest public affairs films, including u.s. residents, spanish-american war, world war and the first ever political ad created by the democratic party. like this is the earliest ad in our collection. may 1958, quadra flex tape. this is the inauguration of color television ad and nbc owned and operated station in washington, d c it was hosted by robert sarnoff

and attended i president eisenhower. during the ceremony, sarnoff slips a switch. cameras you see before you are color cameras. they are now transmitting a black and white picture. by pressing this button, which i now do, cameras are transmitting a live color picture. you you step before them, will be making your first appearance on color television from washington. >> it goes from black and white to color and he tells president eisenhower that we are making two copies on this new kind of videotape for you, mr. president. >> i have a strip of this new tape. i have asked our engineers to make two copies of this program. president, sent, mr. to the white house where your personal retention. the other will be presented to the library of congress so the archive may possess a permanent record in color of this significant occasion.

i think all of us realized in these fast-moving times that it is highly our nations capital attached to every single citizen in this country by the very fastest, best kind of communication. decisions of a nation, not a government, that at one time could tolerate three or four demand almost now instantaneous reactions. >> that is the copy we have here. our engineers reese lee did a new transfer of it -- our engineers recently did a new transfer of it and years later, we're still able to copy this videotape.

is just tremendous amounts of material waiting for a new generation of researchers to discover it and make something meaningful of it. there's a lot of stories that and we are eager to make more of it available are people to discover and it really and tell us more about what we have. ♪ >> florence harding went said she only had one hobby and that was warren harding. she was a significant force in her husband's presidency and adept at handling the media despite hardships and scandals,

and herand's infidelity own poor health, she would help define the role of the modern first lady. florence harding, tonight on c-span is original series, examining the-- ladies who influenced the presidency." that's tonight on "american history tv" on c-span3 . >> coming up next, richard horton examines president truman's decision to drop the atomic bomb on hiroshima and nagasaki. he looked at the promises franklin roosevelt made during the yield a conference. richard thornton is the president at the institute for the study of strategy and politics which is to dissident. this is a portion of a symposium that focused on august, 1945 in asia and the pacific, marking

the 70th anniversary of the end of world war ii. it's about one hour. >> today, we have professor thornton from george washington university. he is a presidential historian and he has written books on the presidency of carter, nixon and reagan. also a book on truman and the korean war, which today, he's going to discuss truman and the end of world war ii. mr. thornton: although there are many books on truman's decision to shop the atomic bomb, there are two overarching determinations. one is the official view that it was done to shorten the war and save