Design of Everyday Things [79]
6.1 Design Subtleties. In the older Bell System instrument, the prongs that held the receiver also prevented the switch hook from being accidentally depressed. More recent telephones often lack such niceties.
Mark is sitting at his desk when the phone rings. “Hello,” he answers. “Yeah, I can help you—let me get out the manual. ”He reaches, pulling the telephone with him. Bang! Crash! The phone falls on the floor, hanging itself up. “Damn,” mutters Mark, “I don’t even know who that was.”
THE TYPEWRITER: A CASE HISTORY IN THE EVOLUTION OF DESIGN
“Among all the mechanical inventions for which the age is noted, none, perhaps, has more rapidly come into general use than the typewriter.... The time is coming when it will almost, or quite as much, supersede the steel pen as that has the good, gray goose quill.”3
The history of the typewriter is the story of dedicated inventors in many countries, each striving to develop a machine for rapid writing. They tried many versions in their struggle to get the one that fit all the constraints—that worked, could be manufactured at reasonable cost, and could be used.
Consider the typewriter keyboard, with its arbitrary, diagonally sloping arrangement of keys and its even more arbitrary arrangement of letters on the keys. The current standard keyboard was designed by Charles Latham Sholes in the 1870s. The design is called the “qwerty” keyboard (because in the American version the top row of letters begins with “qwerty”), or sometimes the Sholes keyboard. The Sholes typewriter was not the first, but it was the most successful of the early versions; it eventually became the Remington typewriter, the model upon which most manual typewriters were constructed. Why such a weird keyboard?
The design of the keyboard has a long and peculiar history. Early typewriters experimented with a wide variety of layouts, using three basic themes. One was circular, with the letters laid out alphabetically; the operator would find the proper spot and depress a lever, lift a rod, or do whatever other mechanical operation the device required. Another popular layout was like the piano keyboard, with the letters laid out in a long row; some of the early keyboards, including an early version by Sholes, even had black and white keys. Both the circular layout and the piano keyboard proved awkward. In the end, a third arrangement was adopted by all: a rectangular arrangement of keys, still in alphabetical order. The levers manipulated by the keys were large and ungainly, and the size, spacing, and arrangement of the keys were dictated by these mechanical considerations, not by the characteristics of the human hand.
Why did the alphabetical ordering change? To overcome a mechanical problem. When the typist went too quickly the typebars would collide, jamming the mechanism. The solution was to change the locations of the keys: letters such as i and e that were often typed in succession were placed on opposite sides of the machine so that their bars would not collide.4 Other typewriting technologies did not follow the qwerty arrangement. Typesetting machines (such as the Linotype machine) use a completely different layout; the Linotype keyboard is called “shrdlu,” after the pattern of keys it follows, and is modeled after the relative frequency of letters in English. This was how hand printers arranged the letters that they would remove from bins and insert manually into the printing forms. Ah, yes, the natural evolution of design.
Not all early keyboards had a backspace, and the “tabulation” key (“tab” on modern keyboards) was a revolutionary breakthrough. The first