Back in Time - Preparing Lessons

Ditto machine

This time of year always takes me back to the days of preparing lessons and informational handouts for my students. Thankfully, technology has made it easier for today's educators to prepare lesson for their classes.

In order to have multiple copies of worksheets and information for my students, I used a ditto machine from the early 70s to nearly the late 80s. The machine was notorious for jamming if the ratio of duplicating fluid was not matched correctly to the speed of the turning drum on which the ditto master was secured. Many times, the sheets would come out blurry and quite damp. I can still vividly recall the smell of the duplicating fluid. The first machines I used were hand crank, but eventually, the school(s) replaced them with electric ones.

The ditto masters were messy to prepare. I often would write on the master rather than type because any error or mis-strike on the typewriter required scraping of the thick blue material off of the white base. Sometimes I resorted to cutting out the error with a razor blade or covering the error with Scotch tape. Nonetheless, the blue gunk would ultimately end up on the cuffs or front of my blouse and on my hands.

Thermofax machine - first used in the 1950s - was the predecessor
 of the office copy machine

Another machine that was used in the late 70s was the Thermofax. This allowed a ditto master to be prepared from a plain piece of paper. The document was placed inside a special sleeve and fed through the machine which burned the document on a thin master that could then be used on the ditto master machine. The Thermofax also could be used to prepare transparencies for the overhead projector. Because it was more expensive to use the Thermofax machine, teachers were encouraged to use the ditto machine instead. While more convenient to use, the copies were not too sharp on the master created by the Thermofax.

It wasn't until the early 1980s that photocopy machines were widely available in the schools where I taught. Even then, because of cost, the use of photocopiers was discouraged, and the mimeograph was used until nearly the mid to late 80s.

Another machine that was used to print higher quality copies was the mimeograph machine. The stencils used in this machine were longer than a ditto master, and any errors were corrected with a correcting fluid. A stylist could be used to add larger fonts or numbers. This type of machine was usually used to produce school newsletter or newspapers and/or brochures.

Do you remember ditto masters, mimeograph or Thermofax machines?