Every day 95 million new images enter Instagram's torrent of selfies, camera-friendly cats, and food portraiture. This snapshot surge is not without precedent. Consider the story of the stereographAmerica's earliest mass-produced photograph craze.

First, some background.

Photography is a French invention, developed by Louis-Jacques-Mandé Daguerre and officially recognized in early 1839.

Newspaper features describing this new technology reached Philadelphia later that year. Many readers disbelieved such a process was possible.

U.S. Mint employee Joseph Saxton assuaged any doubts. With a cigar box, a burning glass lens, and a silver-coated metallic plate, the Philadelphian peered out of an upper window at the Mint and captured an image of two partially blurred buildings.

The result: The oldest extant photograph in North America.

"Catching a shadow is a thing no more to be laughed at," Godey's Lady's Book avowed in 1840.

Early "daguerreotypes" like Saxton's were expensive and irreproducible. By midcentury, however, technical innovations removed these barriers to widespread popularity. A particular type of photograph soon emerged as the country's most prevalent.

Also known as "doubleeyed" or "twin pictures," stereographs feature two nearly identical images. An illusion of three-dimensionality is produced when a viewer peers through a special lens.

For a sense of the optical effect, think of your childhood View-Master and Tru-Vue.

"The mind feels its way into the very depths of the picture. The scraggy branches of a tree in the foreground run out at us as if they would scratch our eyes out," remarked Oliver Wendell Holmes, inventor of an inexpensive viewer. "The first effect of looking at a good photograph through the stereoscope is a surprise such as no painting ever produced."

Cheap to produce compared to their daguerreotype counterparts, stereographs allowed millions of Americans to imagine themselves investigating Mayan ruins in Honduras, observing Buddhist ceremonies in Japan, and exploring the tombs of Egypt.

The latest technological marvels and natural wonders — skyscrapers, railroads, the Grand Canyon, Yellowstone — were also brought to life through the portal of a stereoscope.

Armchair explorers weren't the only group to benefit from the technology. Stereographs offered a unique view for news junkies and captured events including the Civil and Spanish-American Wars, the Centennial Exhibition, and the Great Chicago Fire.

Befitting the technology's origin in Britain, many credit Queen Victoria with internationalizing awareness of stereographs. The monarch found herself smitten after gazing through a stereoscope displayed at the 1851 Great Exhibition in London.

Photographers on both sides of the Atlantic, however, had been aware of the process prior to its royal endorsement.

Among those "light writers" working in Philadelphia's dozen-plus photography studios, the city's most prominent included a pair of German immigrants, William and Frederick Langenheim.

The brothers had long established a reputation for artistry and promotional savvy. Operating out of their studio at the Mercantile Exchange along Third and Walnut Streets, they counted President John Tyler as a customer. So convinced of their skill, the Langenheims mailed their five-piece panorama of Niagara Falls to Daguerre himself.

Armed with a patent for producing paper photographs, the brothers founded the American Stereoscopic Co. and unveiled their "twin pictures" in 1850 — one year before Queen Victoria became enamored with the stereograph.

The images continued to pique the public's interest for more than six decades.

The Langenheims were far from the only photography pioneers in the city. Robert Cornelius, a lamp-maker, snapped the first self-portrait, or selfie, in his family's Philadelphia store.

Vincent Fraley is communications manager for the Historical Society of Pennsylvaniavfraley@hsp.org