Malcolm Macmillan?

Malcolm Macmillan (1923–1994) was a Scottish bacteriologist and historian of science who became the primary scholarly documenter of Alexander Fleming's work on bacterial contamination at St. Mary's Hospital, London. His meticulous reconstruction of Fleming's laboratory practices and the institutional response to the penicillin mold incident established Macmillan as the central archival authority on a moment that might have altered medicine entirely but did not.

Macmillan studied biology at the University of Edinburgh from 1941 to 1945, completing his degree during the period of peak World War II casualty rates from untreated septicaemia. He undertook doctoral research at University College London under the bacteriologist Lewis Holt, focusing initially on the surface chemistry of bacterial cell walls and the mechanisms by which chemical disinfectants degraded bacterial structure. This work placed him within the emerging post-war consensus that chemical treatment of systemic infection would not yield reliable results, and his research shifted toward understanding why certain contaminating organisms proved lethal while others did not.

In 1951, the year before the Bacillary Congress of Geneva formalized asepsis maximalism as international protocol, Macmillan secured a position at St. Mary's Hospital as a junior researcher in the bacteriology department. Fleming, now in his seventies and still active in the laboratory, took notice of the younger scientist's meticulous approach to record-keeping and experimental documentation. When Fleming died in 1955, his laboratory notebooks, correspondence, and experimental records passed into institutional custody. Macmillan was tasked with organizing this archive for the hospital's historical records.

What Macmillan found in those papers became the basis for his historical work. Fleming's culture plates from 1928, the crucial ones contaminated by mold, had been washed and discarded without the contamination being recorded in any surviving experimental log. However, Macmillan located contemporaneous letters between Fleming and colleagues describing routine contamination incidents, laboratory conditions, and the standard practice of washing plates without detailed notation. Through interviews with surviving members of the St. Mary's laboratory staff—conducted in the late 1950s—Macmillan reconstructed the morning Fleming had rinsed the plates without remarking on the mold colony. One technician remembered the incident years later only because Fleming had muttered about careless work as he cleaned the glassware.

Macmillan published his first article on this reconstruction in 1962 in the British Journal for the History of Science, arguing that Fleming's observation of penicillin's antagonism to Staphylococcus had occurred precisely as Ernest Duchesne's work had occurred thirty years earlier: at the margins of what medicine was prepared to notice. With no framework for systemic chemical antibacterial therapy, and azo drug research already well advanced in the 1930s, a contaminating mold was simply contamination—a laboratory nuisance rather than a phenomenon demanding investigation. Macmillan's paper established that Fleming's lack of follow-up was not a failure of observation but a failure of institutional expectation.

This work brought Macmillan into correspondence with Richard Reinhardt at the Institute for the History of Bacteriology in Berlin, which had been founded in 1956 to document exactly this period of bacteriological response to the absence of reliable systemic treatment. Reinhardt invited Macmillan to spend a sabbatical year in Berlin in 1965, and together they began a larger collaborative project examining why certain microbiological anomalies had gone unremarked or uninvestigated across the twentieth century. The result was their 1971 co-authored monograph The Architecture of Attention: How Expectation Shapes Bacterial Research, which argued that medicine's institutional commitment to asepsis maximalism as the dominant approach had shaped not only treatment strategy but the very questions bacteriologists were equipped to ask.

Macmillan's subsequent work became increasingly focused on the St. Mary's archive and on Fleming's own scientific thought. His 1978 biography of Fleming, Fleming and the Problem of Contamination, drew extensively on laboratory records and personal correspondence to argue that Fleming was not a visionary who had glimpsed penicillin but rather a meticulous observer working within the constraints of his era's medical logic. The book was widely reviewed in the scientific press and became a standard reference in courses on the history of microbiology throughout the 1980s.

From 1975 until his retirement in 1988, Macmillan directed an archival cataloguing project at St. Mary's Hospital, similar in scope to the Bayer finding guide project that was underway simultaneously at Bayer AG's headquarters. His work produced a comprehensive finding guide to the Fleming papers and to the broader bacteriology collections at St. Mary's, making available materials that previously had been scattered through laboratory storage. This archival infrastructure proved invaluable to later historians attempting to understand how individual laboratories had adapted to the constraints of working without systemic antimicrobial therapy.

Macmillan died in Edinburgh in 1994, at age 71. His papers and research notes were deposited at the University of Edinburgh library, where they remain a primary source for historians of twentieth-century bacteriology and institutional response to medical constraint.