Publication and its attendant excitements have taken up much of the past month, and I have a stack of punctuation-related matters to catch up with. Without further ado, let’s get on with the show!
Readers of Shady Characters (whether in book or blog form) will recall that the octothorpe (#) came by its rather esoteric name courtesy of the creation, in the 1950s, of the push-button telephone keypad. The engineers of Bell Labs had designed a 4 x 4 grid of buttons where each row and column was assigned a unique audible frequency; when pressed, a button produced a tone composed of the frequencies corresponding to its location on the grid. Early production handsets had only ten buttons — the digits 0–9, arranged in the familiar inverse-calculator layout — while later versions added ‘*’ and ‘#’ buttons to yield a neat 3 x 4 grid. (Military and other speciality handsets used all four columns.) The story, as told by two separate Bell Labs employees, goes that there was no unambiguous name for the ‘#’ and so, for the purposes of training and documentation, it was necessary to invent one: “octothorpe” was the result, and its place on the soon-to-be ubiquitous telephone keypad assured its survival into the future.
Upon watching a recent video on the subject, however, I found myself drawn back to the design of the keypad itself. As I discovered when first researching this topic, its grid-like arrangement was no accident. Early investigations found that call routing equipment was easily confused by human voices, and so composite tones of two or more frequencies were required. Pairs were found to be sufficient, though they worked best when each pair comprised frequencies chosen from mutually exclusive high- and low frequency groups. In the resulting grid layout, rows got the low tones and columns the highs.1
With that in mind, then, take a look at this rogues’ gallery:
These are the seventeen candidate keypads that Bell considered in the years leading up to the unveiling of their new Touch-Tone handsets. Taken from a 1960 paper named Human Factors Engineering Studies of the Design and Use of Pushbutton Telephone Sets, written by one R. L. Deininger, these layouts were tested for speed, accuracy and preference by test cohorts composed of randomly selected Bell Labs employees.2
Five layouts were chosen as being especially promising in terms of speed, accuracy, and preference among the test cohorts: IV-A (“three-by-three plus one”); II-A (two horizontal rows); IV-B (two vertical columns); VI-C (“telephone”), and I-C (“speedometer”). Of these, the grid-like “three-by-three plus one” layout was selected for further study by dint of possessing “certain engineering advantages”; though Deininger does not spell it out, those advantages must surely have boiled down to simplicity with which its buttons could be made to actuate the oscillators that generated their characteristic tones.
What I find intriguing about all this is that the ‘*’ and ‘#’, the auxiliary keys that we now take for granted on our telephone keypads, are utterly absent from this otherwise comprehensive experiment. Where would they have ended up if, say, the “speedometer” or “telephone” layout had been selected? Would the number keys now be found orbiting the “little star” of the asterisk, held in place by the gravity of the pound sign? Or would they have been relegated to the bottom of the telephone like an especially terse, cryptic footnote?
For more on this story, head over to the Numberphile YouTube channel for their illuminating video on Bell Labs’ work on telephone keypad layouts. As a bonus, listen out for a particularly entertaining anecdote about how the head of their Human Factors department settled on the minimum acceptable length of telephone cords. It’s well worth watching!
In other (and slightly belated) news, last month Peter Robinson wrote an opinion piece for The Guardian on the interrobang, describing it as “the ultimate symbol to express excitement and outrage in our shockaholic era.” I’m reminded of Remington Rand’s description of the mark as they prepared to make it available on their typewriters back in 1968:
[…] Interrobang is already receiving favorable comments from typographers who are said to commend it for its ability to express the incredibility of modern life.3
If the “incredibility” of our “shockaholic” era continues to increase apace, soon there will be no punctuation capable of expressing it. Joking aside (or not), Robinson does come up with the best use of the interrobang since the WSJ’s “Who forgot to put gas in the car‽”,4 writing: “Elsewhere, ‘I Can’t Believe It’s Not Butter!’ could rebrand as, simply, ‘Butter‽’ ”
In a happy coincidence, Conrad Altmann, a long-time friend of this blog, has posted a stylish new interrobang T-shirt for your consideration on Cotton Bureau. If you’d like to help Conrad see his shirt printed, head over there to reserve one for yourself.
Thanks for reading!
- L. Schenker, “Pushbutton Calling with a Two-Group Voice Frequency Code,” The Bell System Technical Journal, pp. 235-255, 1960. ↩
- R. L. Deininger, “Human Factors Engineering Studies of the Design and Use of Pushbutton Telephone Sets,” Bell System Technical Journal, vol. 39, iss. 4, pp. 995-1012, 1960. ↩
- “Interrobang Is Newest Mark Of Punctuation,” Univac News, 1968. ↩
- “The Missing Symbol,” Wall Street Journal, 1962. ↩