NARRATOR: This exhibition case features very early daguerreotypes from the first decade of photography in the United States.

JEFF ROSENHEIM: So, what’s a daguerreotype? It’s a technological marvel.

NARRATOR: The image is formed on a sheet of silver-plated copper treated with light-sensitive mercury and iodide vapors. Curator Jeff Rosenheim:

ROSENHEIM: There’s no negative. It’s not printed. The plate that was in the camera that sat in the photographer’s studio with the subject is what you’re looking at. So, the breath of the photographer and the breath of the sitter are combining with the silver image on the plate, and that’s what we’re looking at here.

NARRATOR: See the man with the blue necktie? It’s the second image from the left.

ROSENHEIM: What’s lovely about this picture is that this man in his double-breasted overcoat, he’s clean-shaven, he’s gotten his hair all groomed for the portrait.

It’s probably the first portrait he has ever had of himself. And he strikes a pose really quite right out of painted portraiture.

And he even wears a smile, which is seldom seen because the exposure times were so long. This wasn’t made in a fraction of a second. It was made in seconds or tens of seconds. When photography was born, you had to hold extremely still.

NARRATOR: Maybe you’ve noticed that these daguerreotypes have a highly-reflective, almost mirror-like surface.

ROSENHEIM: Oliver Wendell Holmes, the writer, said that what he considered so amazing about a daguerreotype was that it was a mirror with a memory.