I’m afraid I have something of an ulterior motive in selecting Melvin Calvin as my chemistry hero. There are many brilliant chemists shrouded in the mists of 20th century history, and it was only because of an amusing story I was told by the legendary John Kilcoyne at this year’s Cheltenham Science Festival that I began to take serious notice of Calvin’s work. That said, Calvin is a man worthy of standing alongside some of the other giants of the chemical sciences that have already been featured in this series of blog posts. Most scientists will instantly associate Calvin with the famous biochemical cycle, named in his honour, which he elucidated. In the 1950s, when Calvin carried out his work, little was known about the details of photosynthesis and the idea that carbon dioxide was the feedstock for making plants’ sugary foodstuffs wasn’t widely accepted.
Calvin set about conducting tortuously complex experiments to assess the impact of everything from light, pH, carbon dioxide and oxygen on photosynthesis. All this needed an elaborate array of instruments and Calvin’s 1955 JACS paper – kindly provided for me by Tracey Jenkin at the Worsley Chemical Library at Bristol University – has a figure showing one such set up. It looks like something a stereotypical mad scientist dreamt up and was undoubtedly exacting both to set up and use on a daily basis.
Although of course I wasn’t lucky enough to ever meet Calvin (he died in 1997), according to John Kilcoyne he was a serious man with little patience for jokes or pleasantries.This contrasted starkly with his graduate student A T Wilson; a bit of a practical joker. Wilson reputedly made a wager with the departmental secretary that he could sneak in a picture of a man fishing in one of the reactors in the diagram without his supervisor realising. He won his bet and the fishing man is still in the diagram. Calvin never found out.