News Flash! 26 Mar 2011
A gentleman who "worked with Doug Engelbart from 1973 till 1984, first at SRI-ARC then at Tymshare Augment, when we were bought out in 1978" has positively identified the Mystery Mouse at last!
"That Mystery Mouse is a prototype that we developed at SRI. This was done so we could mass produce a cheaper model, so we came up with the plastic wheels, the cheap square buttons, the ribbon cable and the DB25 with only pins present that were used. I believe we were making our metal wheeled mouse for $400.00 each, which is astronomical compared to what we pay for mice today. I have one of the mystery mouse and I also have one of the original metal wheeled mouse. The cheap mouse experiment did not work as the wheels didn't work as well as the metal ones, the ribbon had problems, and the square buttons wouldn't work most of the time.
"I think we only produced ten of those prototype Mystery Mouses. You know where two are located, but where are the other eight?"
Thank you for solving the mystery after all these years.
A mysterious mouse in private ownership operates with perpendicular wheels like the original Engelbart mouses. The mouse looks like it has aged from beige to golden. Three square black buttons set closely on the finger edge of the rounded plastic case. The underside structure is metal. Two white wheels track the X-Y coordinates.
A rounded nut provides the third point of contact for gliding. The flat cable comes out of the right side at the button edge, leading to a DB25 pin plug. One of the pins in the plug is longer than the others and several pin positions are empty.
The owner writes that the mouse came with "a very peculiar Z-80 based computer from Product Associates Inc. (PAI). The serial number on it (100) leads me to believe it is either a prototype of some sort or one of a limited run." Thank you for the info and the use of the photos, Gary.
The original Engelbart mouse was constructed of wood with metal wheels and one button [photos: Bootstrap Institute]. Subsequent versions were plastic models with three small round buttons [photo: Bootstrap Institute].
According to an interview with Ron Cude by the Digibarn publisher Bruce Damer, this mouse was made by Jack Hawley before he went on to invent the ball mouse. The owner solicits any information about it and purchase inquiry—send to email@example.com.