A small piece of history discovered hidden among a dead man's possessions has been sold by his daughter at auction.
Photographs of the construction of Teesside's nylon works in the late 1940s went for £100.
Mike Satow, an engineer and general manager for ICI, was part of the team which built the Wilton Nylon Plant in 1947.
Photographs he took of the factory were sold with a packet of sample pellets and a piece of the first nylon ribbon made there.
Mr Satow's daughter, Clare, said: "These things are much better in the public or with a historian.
"This is more significant in the outside world than it is in a chest of drawers in my attic."
Ms Satow learned a lot about her father from the enormous piles of papers and photographs she inherited.
He was posted to India with ICI in 1956, with his wife and children following a year later.
"He just developed an insatiable curiosity about the fate of steam engines built in this country and shipped out to India," she said.
"He almost seemed to go on a sort of tiger hunt, looking for derelict steam engines."
In 1970 Mr Satow became honorary adviser to the Rail Transport Museum in New Delhi, Asia's first railway museum and "went backwards and forwards" between England and India.
His passion was documented by the BBC five years later in a programme celebrating India's railway system.
Back in the north-east of England after retirement he built a replica of George Stephenson's famous steam locomotive, Locomotion, which is still housed at Beamish Museum in County Durham.
"It was actually built on the nylon works site," his daughter said. "It was the sort of thing he did."
Her father, who "always whizzed around and was always off to a meeting", died in 1993.
"I'm enjoying going through his papers and learning a bit more about him," she said. "It's quite nice to find him now - now that he can't escape."