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University of Minnesota's Scholars Walk
Scholar's Walk

The University of Minnesota recently unveiled its long-awaited “Wall of Discovery,” an illustration-rich installation on the north side of Keller Hall where the EE and CS departments are located.  It connects the core part of campus with a walkway out to McNamara Alumni Center and beyond to the TCF Football Stadium.  I took this route literally four times a week last semester when teaching in a nearby classroom.  I expected to see Mark McCahill and Seymour Cray among the university’s luminaries.  McCahill led the software team that developed Internet Gopher, a distributed means for people around the world to share multi-media content over the Internet prior to the Web’s dramatic expansion in the mid-1990s.  McCahill also invented POPmail, used by my spouse today to access her email on Earthlink, as well as coined the phrase “surfing the Internet.”  Seymour Cray, world famous as a designer of supercomputers, was the technical brains behind many of the early Minnesota computers, including those of the Engineering Research Associates, Univac, Control Data, and Cray Research.  Cray’s schematic for the iconic Cray 1 is the chosen illustration on his plaque. 

Other computing figures along the walkway of University of Minnesota notables include Rolland Arndt, a lead designer for ERA–Univac (CBI papers); John Bardeen, assistant professor of physics during 1938-41, co-inventor of the transistor, and winner of two Nobel prizes (1956 and 1972); Bardeen’s co-inventor Walter Brattain, physics Ph.D. in 1929; information retrieval pioneer Calvin Mooers (CBI papers); polymathic inventor Otto Schmitt; Cray’s right-hand man James Thornton; and Earl Bakken, founder of Medtronic.  I was pleasantly surprised to learn the technical biography of Minnesota native Reynold Johnson.

Reynold B. Johnson (class of 1929) has several impressive claims to fame.  The “Wall of Discovery” emphasized the colorful story of his inventing the classic machine-scored “bubble exam” complete with use of Number 2 pencils, while he was a high-school science teacher in Michigan.  The soft pencils put down a track of conductive graphite that could be read electronically.  In his childhood, he’d used such pencils to short out the ignitions of Model-T automobiles and play havoc with the social life of older sisters and their “gentleman callers.”  IBM hired him to develop these insights at its Endicott Engineering Laboratory, and this work found its way into IBM’s model 805 Test Scoring Machine (see illustration of an early prototype).  It was first used to tally the 1936 New York Regent’s exam, and successive waves of Johnson’s “mark sense” technology have been used in countless exams by innumerable students since then.  In the 1960s optical means for reading student-marked cards became the dominant method for scoring.

Model 805 Test Scoring Machine. Photo Credit: IBM
Model 1805

Johnson moved to California in 1952 and provided leadership for IBM’s newly founded laboratory at San Jose.  His team of researchers initially followed Minnesotan’s lead in using magnetic media on rotating cylinders, but soon the San Jose researchers reconfigured the cylinders into rotating disks, much like oversize long-playing records.  In 1956 IBM announced this invention as the model 305 Random Access Method of Accounting and Control, or RAMAC.  The first magnetic disk was bought by Crown Zellerbach, a West Coast timber concern, in 1956; it had 50 double-sided aluminum disks that were 24 inches in diameter, with a total storage of 5 megabytes.  Johnson later developed, in cooperation with SONY, the basic technology of VHS videocassettes.  He collected more than 90 patents and numerous technical awards, passing away in 1998.

Thomas J. Misa


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