Heart-lung machines are key components of cardiac surgery. Their main purpose is to replace cardiopulmonary functions during surgical interventions in the open heart. While today’s heart-lung machines are robust and reliable devices, their early versions were highly precarious assemblages. When US surgeon John H. Gibbon, Jr. (1903–1973) started to develop the heart-lung machine in the 1930s, minor factors such as the irregular flow of blood through the tubes and vessels of machine and organism could quickly result in death. In fact, throughout all the stages of its development – from Gibbon’s early animal experiments to his successful cooperation with IBM following World War II – the heart-lung machine required meticulous strategies to control the blood flow. Based on new archival evidence, this paper reconstructs the development of the corresponding control systems, situating them within the material culture of their time. It argues that Gibbon’s work crucially relied on devices of and evolved from media technology: Gibbon started out by adopting instruments from telegraphy systems, but increasingly incorporated electronics derived from radio research laboratories. As a result, it will become clear that the heart-lung machine evolved within complex intersections between academic medicine, industrial research, and amateur radio.

Human factors engineering professionalized in the early years of the Cold War due to the development of safety-critical systems—those in which failures would be catastrophic. Often used interchangeably with ‘ergonomics,’ human factors engineering (HFE) not only considers physical comfort in the composition of objects and systems, but seeks to optimize human performance through strategic design principles drawn from psychology, cognitive science, and other fields. The origins of HFE are typically traced to Taylorism, but it was not until the Cold War era that the field became widely researched and implemented in a variety of areas. The American military long held interest in HFE. Earlier called ‘applied psychology’ or ‘human engineering,’ branches developed tactics to improve selection and training techniques; in later years, engineers applied research in the construction of weapons systems and command rooms. By the 1960s, largely due to Cold War imperatives and the development of new computing and communications technologies, many federal, company, and university laboratories were conducting HFE research in efforts to better understand man-machine interactions. NASA, an agency itself borne of the space race between the United States and Soviet Union, has been a key contributor to the development of human factors engineering. Along with pioneering biomedical studies necessary in determining how man would physically venture into space, NASA investigated how displays and controls needed to be placed aboard spacecraft so that astronauts would be best able to process complex information and complete tasks. 

A “silver curtain” of secrecy separated Eastman Kodak’s photographic emulsion researchers from their co-workers and professional colleagues in the Cold War United States. As the popularity of this metaphor among Kodak’s laboratory workers suggests, the firm’s concern about divulging insights into the chemistry of silver halide emulsions partly stemmed from its participation in military initiatives such as project Corona, the satellite reconnaissance program. However, Kodak’s extensive use of secrecy predated the start of the Cold War by more than half a century. As early as the 1890s, the firm had introduced policies of classification, compartmentalization, and fragmentation, while also restricting the mobility of its technically skilled personnel by means of employment contracts and non-compete agreements. While some of these measures were relaxed in the following decades, none was fully abandoned.
Drawing on the Kodak Historical Collection and other newly accessible archival sources, this paper aims to contribute to a better understanding of the relationships between industrial and state secrecy in twentieth-century research and development work. I first demonstrate that, during World War I, Kodak’s emulsion researchers were allowed to collaborate relatively freely with the Army and the Bureau of Standards on the development of aerial photography. Afterward, however, Kodak was no longer willing to support emulsion studies outside of its own closely controlled facilities. Similarly, despite the program’s highly classified nature, project Corona did not involve access or communication restrictions to which Kodak’s emulsion researchers had not previously been accustomed.

 
 In 1903, the Select Committee on Ventilation, appointed by Britain's House of Commons, published a critical review of ‘modern’ ventilation systems. It decried the infamous lack of success engineers had had in ventilating the Houses of Parliament, but, more critically, it noted new statistical information showing that ‘impurity of the air is the most important cause of death’. The document made waves in Britain before traveling across the sea to the United States, where it proved a vital weapon in the armamentarium of artificial ventilation's detractors.

Medical practitioners were quite often among those who eschewed and excoriated artificial ventilation as unhealthy, unsafe, unnecessary and impractical. This was the cause of great consternation among mechanical engineers especially, who despaired that leaving artificial ventilation systems out of hospital construction, or allowing them to lay dormant, was ‘retrogressive’. In cities whose inhabitants increasingly relied on, and breathed, artificial air, medical buildings which continued to rely on windows to provide air were worse than anachronistic. They were dangerously anti-modern.

 
 But medical practitioners had their reasons. This paper recounts the context and content of their resistance to artificial ventilation in the first decades of the 20th century. It highlights related contemporary debates in the construction of subways, ‘skyscrapers’ and other essentials of urban life. And it examines the impact of contemporary theories concerning ‘fresh air,’ which, drawing on air’s earlier status as primarily a therapeutic agent, made manifest the essential difficulties of deciding what ‘fresh air’ actually was in the first place.