Today, the latest photography innovation is something like Snapchat. We take photos so easily and so casually, a photo can be seen once and then disappear.

It's hard to imagine things back in 1839, when it took Joseph Saxton 10 minutes to expose a daguerreotype, the new technology of the time.

Saxton's daguerreotype, the oldest surviving "photograph" made in the United States, is not a dramatic view or composition. It shows Central High School at Walnut and Juniper sitting next to the Philadelphia armory, taken from what was the U.S. Mint at the time, where Saxton worked. His "camera" was composed primarily of a lens and a cigar box.

"A daguerreotype is basically a copper plate with a thin coating of silver on the outside," said Lee Arnold, director of the library and collections at the Historical Society of Pennsylvania. The original is a part of Arnold's collection.

"The technology traveled from Europe," he said, "so this wasn't happening in the U.S. This was a new technology, and he's fiddling with it."

A few months later, a Philadelphia lamp-maker, Robert Cornelius produced a self-portrait. It's also part of the Historical Society's collection.

The photo of Central High School spends little time on display — for reasons of preservation.

"Just like if you keep on banging the Liberty Bell, the crack is just going to get bigger," said Arnold. Time and too much light would make the surface look like a simple mirror, he said. The country's oldest photograph would simply disappear.