The Ditto Machine A spirit duplicator (also referred to as a
Ditto machine ) was a low-volume printing method used mainly by
schools and churches. The term "spirit duplicator" comes from
the alternative term for alcohols, which is "spirits." Alcohols
were a major component of the solvents used as "inks" in these
machines. The spirit duplicator was invented in 1923 by Wilhelm
Ritzerfeld. The best-known manufacturer in the United States was
Ditto Corporation of Illinois, hence that name. A ditto machine
used a solvent like methylated spirits or ammonia to transfer
ink from the master copy (the template, if you will) onto other
pieces of paper. The master copy was a smooth, waxy piece of
paper which was thickly inked when printed. The procedure for
printing on a master was like the reverse of a carbon-copy;
instead of writing on the normal paper and having the carbon
underneath, the text and pictures were printed onto carbon paper
of varying colours to transfer print to the master. If you want
to know exactly ho