Spirit duplicator
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A spirit duplicator is a printer invented in 1923 by Wilhelm Ritzerfeld, which was used for most of the 20th century. "Spirit" here refers to the alcohols that were the principal solvents used in gene
A spirit duplicator machine
A school newspaper published using a ditto machine in 1978
A hand-cranked spirit duplicator from the 1960s
The Duplicating Machine Memorial in Szczecin, Poland, taking the form of a spirit duplicator encased in a desiccated glycerol resin on a concrete pedestal
Mauveine
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Mauveine, also known as aniline purple and Perkin's mauve, was one of the first synthetic dyes. It was discovered serendipitously by William Henry Perkin in 1856 while he was attempting to synthesise
Spirit duplicator
…drum. One master can produce 40 or so good copies; after that, the copies gradually become paler as the colored wax is used up. The usual wax color was aniline purple (mauve), a cheap, moderately durable pigment that provided good contrast, but masters were also manufactured in red, green, blue, and black, as well…
Letter from Perkin's son, with a sample of dyed silk
Professor Charles Rees—wearing a bow tie dyed with an original sample of mauveine—holding an RSC journal named after Perkin