Hectograph

The special aniline dyes for making the master image came in the form of ink or in pens, pencils, carbon paper and even typewriter ribbon.

Various other inks have been found usable to varying degrees in the process; master sheets for spirit duplicators have also been pressed into service.

Hectography, requiring limited technology and leaving few traces behind, has been deemed useful both in low-technology environments and in clandestine circumstances where discretion was necessary.

In the earlier 20th century, the process lent itself to small runs of school classroom test papers, church newsletters and science fiction fanzines.

Before the popularization of spirit duplicators and the mimeograph, there were mechanized hectography machines that used a drum, rather than a simple flat tray of gelatin.

In the final chapters of The Pothunters by P. G. Wodehouse the major characters use a jellygraph to produce a school magazine at very short notice.

Wodehouse assumes his reader knows exactly what a jellygraph is and alludes to its being unattractive: "This jelly business makes one beastly sticky.