Mighty Mouse

A joint Japanese–Swiss development from 1985, ten years before the first production scroll-wheel mouse.

I found fairly detailed product documentation, so we can peek into the thinking of the time. The mouse apparently never left the prototype stage; a few photographs show physical examples.

Five buttons and a separate wheel for making the most effective use of human hand dexterity. Two of the five buttons were more sophisticated, distinguishing a click from a slow, pressure-sensitive press.

The shape resembles the Depraz. Understandably: a round case is the only way to fit a button for every finger.

The authors sought to standardise mice in terms of buttons and commands. Before and after 1985, manufacturers offered anything from one button, as on the Apple Lisa, to three, or even dozens on exotic models. The idea was for the same buttons to mean the same actions on all computers. That eventually happened for two buttons and the wheel; everything else is extra and customisable.

The controls in detail:

Thumb button: motion/scroll. Browse file contents, moving forward or backward through a linearly ordered data set, such as a text file. A quick press advances one page; a slow press scrolls continuously at a speed proportional to pressure.

Index-finger button: pick. Select an object. A quick press selects what the cursor points to; a slow press reveals increasingly detailed information, for example through zooming. Magnification is proportional to pressure.

Middle-finger button: menu. Display a pop-up or context menu.

Ring-finger button: undo. Cancel the last user operation and return to the preceding system state.

Little-finger button: quit. Exit or end an operation.

Thumb wheel: angle. Change the cursor's angular orientation on screen.

I'll put the complete document in the comments.

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