['kɔpigrɑ:f]
n.
油印机

Copygraph \Cop"y*graph\, n.
A contrivance for producing manifold copies of a writing or
drawing; -- made obsolete by later developments in copying
technology; see {xerography}.
[1913 Webster +PJC]

Note: The writing or drawing is made with aniline ink on
paper, and a reverse copy transfered by pressure to a
slab of gelatin softened with glycerin. A large number
of transcripts can be taken while the ink is fresh.

Various names have been given to the process [the
gelatin copying process], some of them acceptable
and others absurd; hectograph, polygraph,
copygraph, lithogram, etc. --Knight.