The "aha" moment and initial experiments in 1983 through which Kary Mullis developed the idea of polymerase chain reaction (PCR) are a well trodden story.
"Mr. Cycle," a 1985 prototype, is shown here without its accompanying hot and cold water baths (Mullis says he?s unsure who affixed the "California Dreamin" bumper sticker.) This was the first PCR device resulting from the PerkinElmer Cetus Instruments (PECI) collaboration. It was not fully automated. After each thermal cycle, an operator had to add fresh enzyme because heat damaged the polymerase. Later, Cetus scientists David Gelfand, Susanne Stoffel, Frances Lawyer, and Randall Saiki patented the heat-stable Thermus aquaticus polymerase (Taq),