The spirit duplicator is a peculiar yet enchanting machine used mainly in institutions during the 20th century.
Past and present
he spirit duplicator was invented and patented in 1923 by Wilhelm Ritzerfeld in Germany. Based on the hectograph (further described below in Other duplicators), the machine used carbon paper and dissolvent instead of a gelatin pad to create inexpensive prints (see Cole, D.J. / Browning, E. / Schroeder, F.E.H. (1948): p. 84, Kormuki, J. Z. (2017): p. 40).
The most noticable aspect about the spirit duplicator, which is part of its nostalgic mystique, was probably the smell of the dissolvent emanating from the printing process. It consisted mainly of methyl alcohol (a highly volatile liquid) and possibly caused the school personnel and frequent users of the duplicator to suffer from “[…] headaches, dizziness, nausea, blurred vision and other ominous symptoms“ (Zorn, 2007). The smell was so distinctive that it became part of the machine’s identity and inspired the name spirit duplicator.
Copies were produced directly from the original, by placing a sheet of carbon paper below before writing (or drawing) on it. The carbon paper then created a mirrored image on the back of the original, which was called the master sheet or master. The master was then attached to the machine’s drum. By rotating the drum, the volatile liquid moistened and slightly dissolved the ink, allowing a small quantity of it to be transferred to sheets of paper and therefore create the copy. Is was possible to create to 300 copies that became fainter with each transfer, before the ink dissolved completely (see Cole, D.J. / Browning, E. / Schroeder, F.E.H. (1948): p. 84).
“The smell was so distinctive that it became part of the machine’s identity and inspired the name spirit duplicator.”
It was common, especially in the United States, to refer to the machine as Ditto or Ditto machine, which was the name of the largest manufacturer in the US: the Chicago-based company called Ditto, Inc. The name of the manufacturer became a generic trademark (see Zorn, 2007). In the United Kingdom, the machine was produced by the Associated Automation Ltd and also known as Banda. The Canadian version of the spirit duplicator was Copyrex, promoted by its manufacturer as liquid duplicator. Dupleco was the name of the Italian model and was promoted as alcohol duplicator. In Germany it was manufactured by Geha and Trommler. In the German language, the machines are also called Matritzendrucker (master printer) or Blaudrucker (blue printer), making reference to the typical indigo ink provided by the aniline dye of the carbon paper.
By the end of the 20th century, the use of spirit duplicators declined (see Zorn, 2007). The xerographic copying machine became affordable and produced better quality copies in shorter time. But the charm of spirit duplicators remained. There is still an occasional demand for a print with a soul, or as Kormuki (2017: p.41) puts it: „[…] if you want to make a print that has character and aesthetic presence, is memorable and worth keeping, then old school is for you“ (Kormuki, 2017: p. 41).
Cole, D.J. / Browning E. / Schroeder, F.E.H. (2003). Encyclopedia of modern everyday inventions. Westport, Connecticut: Greenwood Press.
Kormuki, J. Z. (2017). Risomania—The new spirit of printing (first edition). Salenstein: Niggli Verlag.
Zorn, E. (2007). That ditto high is harder and harder to duplicate. Retrieved February 22, 2018, from Chicago Tribune: http://blogs.chicagotribune.com/news_columnists_ezorn/2007/01/ditto_machines_.html