Wheel charts, calculators, information discs, spinners – what DO you call these things?

Have you ever thought about the difficulties of manufacturing and marketing a product that doesn’t have a name? I don’t mean a totally new product for which you can invent a name and market the product from scratch. I mean a product that has been around for over 600 years but it still doesn’t seem to have a universal, generic name. What can the product be? You will have seen them – two or more circular pieces of card, joined at the centre with a metal eyelet and which turn to reveal printed information through an aperture. The Oxford English Dictionary calls them “volvelles” but unfortunately, it seems that they didn’t tell anyone else!

You can imagine this conversation going on in the pub:

“So, what business are you in?”

“Well, we make volvelles.”

“Oh really, and what exactly is a volvelle?”

“Well, it’s a wheel chart.”

“And what’s a wheel chart?”

“Well, some might call it a ready reckoner.”

And so it goes on!

So, the big problem with volvelles is that absolutely no-one calls the product a volvelle. “Wheel charts” is a term which is reasonably common in the USA but again, not everyone in the USA calls them wheel charts and it’s not a term that is used much in the UK. So what do you search for in order to find them?

We been making them since 1992 and originally referred to the products as “eyeletted discs” but others were calling them calculators, information discs, ready reckoners and spinners. I went on Google in search of enlightenment and as “Wheel Charts” seemed to be a popular generic term on US websites we adopted “Wheel Charts” as the product’s name.

However, it transpired that our counterparts in the USA have the same problem. Look at this snippet from the website for Datalizer Slide Charts:

How Did You Search For Us?
Everybody knows our products by a different name. What names did you use to search for us?
Circular Calculators, Circle Charts, Color Wheels, Conversion Charts, Data Dials, Data Disks, Datalizers, Data-lizers, Dial Charts, Dosing Guide Charts, Graphic Calculators, Information Dials, Nomographs, Medical Calculators, Metric Conversion Slide Chart, Plastic Graphic Calculators, Promotional Slide Guides, Slide Calculators, Slide Charts, Slide Guides, Slide Rules, Slide Wheels, Sliders, Slip Charts, Wheel Charts, Technical Calculators, Wheel Charts, Wheel Calculators..

The issue is far from cut and dried! Further investigation was called for and my next port of call was an extremely well researched book “Reinventing the Wheel” by Jessica Helfand.

“Reinventing the Wheel” is a book on the subject of paper wheel charts or circular ephemera of the 20th century. It is a fascinating book if you are into paper and cardboard engineering it would be an interesting addition to your own library. However, whilst the author often refers to the product as a wheel chart, her research tells her that the original term is probably a “Volvelle”.

In her book (p18) she says, “The Oxford English Dictionary traces the etymology of the word volvelle to the medieval Latin, “volvellum” or “volere” – to turn – describing it as “an old device consisting of one or more movable circles surrounded by other graduated or figured circles, serving to ascertain the rising and setting of the sun and moon, the state of tides etc.”

However, Ms Helfand goes on to list over thirty other names by which the product has been known including: fact finders, trouble shooters, locators, calculators, slide rulers, convertisors, circular interfaces, calendials and dynameters.

So, going back to my original question, what DO you call these things?

Information Discs and wheel charts