In 1877, the Autotype Company of London published a shilling manual with an unusual sales pitch: their photographs would outlive you, your children, and quite possibly the building they hung in. J. R. Sawyer, writing for the company, declared their mission plainly:

"to remove from the beautiful and popular art of photography the stigma of want of permanency in its results."

That "stigma" was very real. Victorian silver-albumen prints — the standard commercial photograph of the era — began yellowing and fading within a decade. Family portraits made in the 1860s were visibly rotting on parlor walls by the 1880s. The industry had a permanence crisis, and the Autotype Company believed they had solved it.

Their process, descended from Joseph Swan's patent (whose lapse Sawyer notes will "very widely extend the practice of permanent printing"), abandoned silver entirely. Instead, they used gelatin sensitized with potassium dichromate and mixed with carbon black or other permanent pigments. When exposed to light through a negative, the gelatin hardened proportionally. Wash away the unhardened portions, and what remained was an image made of pure inert pigment embedded in gelatin — chemically stable in ways silver never could be.

The Company's ambition was to "popularize genuine works of art by disseminating copies of them throughout the length and breadth of the land" — a Victorian version of mass-market fine art reproduction, betting everything on longevity.

Were they right? Astonishingly, yes. Carbon prints from the 1870s in museum collections today look essentially as they did when made. Meanwhile:

• Silver gelatin prints from the 1950s show measurable silvering-out and yellowing
• Color chromogenic prints (Kodacolor, Ektacolor) from the 1970s have shifted magenta or cyan and lost dye density
• Inkjet prints from the early 2000s have faded visibly under UV exposure
• Your digital photos depend entirely on file formats and storage media surviving — a much shakier bet than a carbon print in a shoebox

So why did carbon printing lose? Because it was fussy. It required transferring a fragile gelatin film from a temporary support to a final paper, then developing in warm water — a workflow that took hours per print. Silver gelatin, invented shortly after, gave you a finished image in minutes. Speed beat permanence, as it usually does.

The technique never fully died. A small community of fine art photographers still practice carbon transfer printing today, and their prints command premium prices precisely because of the property Sawyer sold in 1877: they will still be here in 2177. Meanwhile, the "cloud" where most of humanity now stores its photographs is a promise underwritten by quarterly earnings reports and hard drives with five-year MTBF ratings.

The Victorians solved image permanence in 1864. We forgot on purpose, because convenience won.