As a one-time graphics artist, Greg immediately recognized its contents. In fact, the box contained an array of glass plate photographic negatives in “various states of disrepair,” according to Scott. And they were cheap.
“The seller wanted £5 ($6.44) for them, but you always have to pay less than is being asked,” Greg told the Press Association. “So I got them for £4 ($5.15), silly money.”
Glass plates were the main photographic medium before the invention of cellulose film in 1903. There were two formats: so-called “collodion wet plates” and “gelatin dry plates.” However, they both worked in the same way. In short, their surfaces were coated with a light-sensitive emulsion of silver salts (much like plastic film), which captured images.