Chapter I

A. Introduction -- C.B. van Niel and the Discovery of Science

In the 1920's, the writer Sinclair Lewis believed American society to be in grave danger of spiritual corruption. Material and commercial success, he feared, were destroying nobility of purpose in American society as it became increasingly obsessed with the pursuit of profit. In seeking a source for the restoration of spiritual values, Lewis turned not to traditional possibilities like religion, Victorian moral principles, heroism in war, or classical education, but to a cultural resource more recently established in the United States: the scientist and scientific research. In his novel Arrowsmith (1924), Lewis told the story of the moral and scientific acculturation of a bacteriologist who learns to conceive of science as a spiritual quest for knowledge unsullied by commercial, material, or political interests. The protagonist of the novel, Martin Arrowsmith, acquires this conception of science by embracing the ideals of his mentor, Max Gottlieb, modeled largely on the European physiologist Jacques Loeb. For Arrowsmith, Gottlieb represents the purity of purpose, rigor of practice, and quality of scholarship American scientists admired in their idealized image of German physiology. By committing to these values, Arrowsmith becomes in Lewis's story a moral hero for American society.⁽¹⁾

At the climax of the novel, Arrowsmith is forced to choose between his obligations as a physician to save human lives and his commitment as a scientist to the ideal of pure research. The conflict between these two forms of moral heroism accounts in part for the novel's dramatic force. Under the immediate and unbearable pressures of a terrifying epidemic, Arrowsmith sacrifices his commitment to pure science to distribute a vaccine. In the novel, Arrowsmith is rewarded for his actions by a new position at his research institute: "Then Martin was made head of the new Department of Microbiology at twice his old salary. He never did learn what was the difference between microbiology and bacteriology."⁽²⁾

C.B. van Niel (1897-1986) might have been a better mentor for Arrowsmith than Gottlieb, and a better model for Lewis than Loeb. Van Niel devoted his life to practicing science as the kind of spiritual quest for knowledge imagined by Lewis, and he sought to establish a clear line of demarcation between "bacteriology" and "microbiology." Throughout his life, van Niel endeavored to cultivate microbiology as a fundamental science radically different in outlook and purpose from medical bacteriology. Van Niel envisioned a science of general microbiology based on rigorous experimentation and aimed at the comprehension of nature. He took a subject that was dominated by practical and technical work and endeavored to transform it into a grand theoretical project.

Van Niel was not destined to become a scientist; rather, his social origins presented an obstacle to that career. New opportunities created by the increasing presence of science in Dutch society, driven in large part by the expectation of practical rewards, made his development into a scientist possible. Despite this reality, van Niel viewed the practical applications of science as a danger, because they distracted attention from the value of science as a cultural endeavor.⁽³⁾

Van Niel never fully acknowledged that the practical utility of microbiology created both opportunities and constraints for researchers committed to fundamental research. The ideal of pure science, articulated in the late nineteenth century, proved to be a strategically useful concept for securing institutional resources and social recognition for fundamental research in microbiology, as for other sciences. Successful researchers committed to fundamental studies defined a sphere of action independent of utilitarian concerns, while taking advantage of the opportunities these provided.

Born in 1897 to a middle-class Calvinist family in Haarlem, the Netherlands, van Niel grew up in a circumscribed world with fixed expectations. Neither science nor any kind of serious intellectual life was within the family purview. Van Niel and his family assumed that he would pursue a career in business. Van Niel's father, a partner in a successful furniture company, died in 1905, leaving the care of his three children to his widow and the "family elders." As van Niel perceived it, the elders ruled with absolute authority. "I seriously doubt that the aptitudes and peculiarities of my sister and myself were ever taken into account in the family councils;" he wrote, "the decisions reached were simply imposed by the 'Olympians.'"⁽⁴⁾ It seemed to him a "foregone conclusion" that he would take his father's place in the furniture business. Van Niel's assessment of the situation was no doubt accurate. Social mobility in the Netherlands in the early twentieth century was extremely limited.⁽⁵⁾ As expected, van Niel began a secondary school program that prepared students for commercial careers.

Van Niel accepted this apparent fate without question until 1913 when, he later wrote, "a drastic change occurred."⁽⁶⁾ That summer, his family visited a friend at his country estate in the rural province of Drenthe. This gentleman, unnamed in van Niel's account, had set up part of his estate as a private experiment station, where he compared the effects of various soil treatments on the production of crops. Van Niel accompanied his host frequently that summer, and listened "spellbound" to explanations of the soil treatments. Van Niel later recalled this experience as his initiation to science. "The very fact that one could raise a question and obtain a more or less definitive answer to it as the result of an experiment was a revelation that deeply impressed me," he wrote.⁽⁷⁾

Recognizing van Niel's lively interest and intelligence, this gentleman appealed to the family to allow their son to attend college. This prospect perplexed the family. Technical training appeared to be a more practical course, as the family was acquainted with a financially successful industrial chemist. For this reason, they agreed that van Niel could study chemical engineering at the technical school in Delft. To prepare for this future, van Niel transferred to a secondary school with an academic curriculum that included science courses. At the new school, a capable chemistry teacher encouraged van Niel's interest in science.⁽⁸⁾

In 1916, van Niel entered the Technische Hoogeschoole in Delft (hereafter "THD") in the faculty of chemical engineering. From 1922 to 1928, he studied with Albert Jan Kluyver at the THD's Laboratory for Microbiology. During that period, Kluyver developed a distinctive and productive program of microbiological research that addressed both practical and fundamental problems. Van Niel's conception of microbiology as a general science of life and his ideal of science as a great theoretical project derived from his experience as a student and research associate with Kluyver. These conceptions and ideals established the foundations of van Niel's approach to the practice of microbiology. They provided the core of the science he successfully cultivated for four decades.

In the 1920's, general microbiology occupied a marginal institutional position compared to medical bacteriology and other practical fields concerned with microorganisms, such as public health, the brewing industries, soil microbiology, and dairying. How did the chemical engineering faculty of the THD come to provide a location for a distinctive and productive program in general microbiology?

B. General Microbiology as a "Research Orientation"

Disciplines, research schools, traditions, styles, and investigative streams are all useful concepts that demarcate collectivities of researchers who share intellectual commitments and institutional relationships.⁽⁹⁾ Analytically, general microbiology from the 1870's to the 1940's might be best described as a "research orientation," a concept proposed by historian Lynn Nyhart. She created this concept to describe nineteenth century morphology, which she argues was an important and vigorous research area, but not a discipline. Rather, Nyhart argues, morphology succeeded by "colonizing and maintaining a niche (at times a large one) within existing disciplines, rather than creating a new one."⁽¹⁰⁾ As described by Nyhart, a research orientation represents a recognizable group of researchers engaged in common problems and sharing common attitudes. Conceptually, it identifies an association of researchers that is broader than a research school and looser than a sub-discipline or sub-speciality. The research taken up by the collectivity shares important features, but is less codified than the term "research program" suggests. The term research orientation refers to: "An area of study...[and] the group of people engaged in that area, and the philosophical attitudes accompanying the cluster of problems they are working on."⁽¹¹⁾

From the 1870's to the 1940's, general microbiology displayed many of the characteristics Nyhart ascribes to research orientations. During this period, the theoretical study of microbiology was carried out by practitioners in diverse institutional locations, often as a minor part of their overall research obligations. In only a comparatively few institutions were researchers primarily occupied with general microbiology. Historian Robert Kohler cites only ten institutions in the world where bacterial physiology was systematically investigated before the 1940's.⁽¹²⁾ In contrast, locations for the practice of medical bacteriology could be counted in the hundreds.⁽¹³⁾ Historian Keith Vernon has surveyed the study of microorganisms in England from 1870 to 1940. He concludes that no consolidated discipline of microbiology existed in England until the 1940's. Rather, microorganisms were in studied in a wide range of contexts, including pathology, public health, water analysis, fermentation industries, and dairy and soil science.⁽¹⁴⁾ In the 1920's, most research on microorganisms addressed practical problems such as disease, sewage, water purification, the dairy industry, food spoilage, agriculture, beer-brewing, and wine-making. Theoretical research in microbiology represented a secondary concern in comparison.

At first, however, all study of microscopic organisms was more philosophical than practical in character. It may be said to have begun in Delft. In the 1670's, Antony van Leeuwenhoek (1632-1723), a Dutch draper skilled in lens making, astounded the learned world with his discovery of "animalcules," a whole world of living things visible only through magnifying lenses. In 1675, Leeuwenhoek described a group of minute animalcules that two centuries later were recognized as bacteria.⁽¹⁵⁾ Leeuwenhoek died without revealing his methods of lens-making, which others could not reproduce. In the eighteenth century, the poor quality of microscopes impeded the study of microscopic organisms. Animalcules remained endlessly fascinating but difficult to investigate.⁽¹⁶⁾

In the nineteenth century, technical and conceptual developments contributed a new impetus to the study of microorganisms. A series of improvements in microscope construction and lens fabrication in the 1830's made detailed observations of microorganisms possible.⁽¹⁷⁾ In 1838, the German microscopist and zoologist Christian von Ehrenberg (1795-1876) introduced the term "bacterium" to designate a genus within the "Infusoria," the creatures observed in infusions of hay.⁽¹⁸⁾ At mid-century, the elaboration of the cell theory first proposed by the German botanist Matthias Schleiden and his colleague, the zoologist Theodor Schwann, transformed conceptions of microscopic organisms. Within the framework of the cell theory, many microscopic organisms could be recognized as single-celled organisms. Some of these were designated "protozoa," because their ability to move gave them an important feature in common with animals studied by zoologists.⁽¹⁹⁾

In the 1870's, the German botanist Ferdinand Cohn (1828-1898) reorganized the category "bacteria." In Cohn's scheme, the bacteria were primitive plants distinguished by their small size and apparent lack of internal structure. Further, their mode of reproduction appeared to be simple in comparison to other single-celled organisms. Bacteria reproduced by elongating and then dividing in two. In opposition to a widely-held view, Cohn concluded that bacteria occurred as distinct and discreet stable species, as plants and animals do.⁽²⁰⁾ This conclusion implied that bacteria could legitimately be classified into genera and higher taxonomic categories. Cohn's 1872 article "Untersuchungen über Bacterien" provided a new taxonomy for bacteria. Noting striking morphological similarities between certain algae and colorless bacteria, he concluded that the latter belonged in the Plant Kingdom.⁽²¹⁾ Cohn placed the bacteria into a higher order group he called the Schizophyta, or "fission plants."

By the 1870's, the study of bacteria in a biological context was well underway. However, toward the end of the nineteenth century, two major developments diverted attention from the study of microorganisms from a biological viewpoint: the germ theory of fermentation and the germ theory of disease.

Trained as a chemist, the French scientist Louis Pasteur began studying microorganisms in 1848. By the 1850's, Pasteur and others had accumulated considerable experimental evidence that alcoholic and other fermentation processes were carried out by microorganisms. Contested for the next two decades, the germ theory of fermentation ultimately prevailed. It had both theoretical and practical implications. For manufacturers of wine, beer, and vinegar, it was a revelation. In the late nineteenth century, many microbiological laboratories were established in connection with manufacturing.⁽²²⁾

Similarly, the study of pathogenic bacteria eclipsed research on bacteria from a biological viewpoint. By the 1860's, Pasteur began to suspect that microorganisms were involved with disease. In the 1870's, he obtained evidence that microorganisms caused disease. This research diverted his attention from the fundamental questions that had led to his interest in microorganisms in the first place.⁽²³⁾

Working independently, the German medical doctor Robert Koch developed a germ theory of disease at about the same time. In the 1870's, Koch, then an unknown country doctor, began conducting investigations of the disease of anthrax in cows. In 1876, he went to Ferdinand Cohn's laboratory to discuss his results. Koch's experiments convinced Cohn that a specific strain of bacteria was the cause of anthrax. Cohn published Koch's first papers in the journal that he had founded in 1870. Koch went on to isolate the tuberculosis bacillus in 1882 and the cholera bacillus in 1884. These discoveries, sensational at the time, demonstrated to the public and to the scientific and medical elite that research on bacteria was likely to be extremely important.

The words "bacterium" and "bacteriology" came into common use with the emergence of the germ theory of disease after the 1870's. German in origin, these terms were favored by those engaged in medically-oriented work. The French preferred their own terminology and offered en revanche the terms "microbe" and "microbiology." The term "microbiology" implicitly included the study of fungi, algae, protozoa, as well as bacteria, and was often used in connection with industrial or agricultural research. Some practitioners considered bacteriology to be a sub-discipline of microbiology. Despite their different connotations, the terms were often used interchangeably.

The successful promotion of the germ theory of disease exerted a forceful impact on the subsequent development of the study of microorganisms. Both Pasteur and Koch won substantial institutional rewards on the basis of their research. In 1888, the Pasteur Institute, financed by public subscription, was founded in Paris. The Pasteur Institute provided an institutional base for research on both medical and general microbiology. In 1891, Koch became director of the newly established Institute for Infectious Disease, under the German state's public health organization. He and his students came to dominate medical bacteriology in Germany.⁽²⁴⁾ This resulted in the almost complete neglect of the biological study of bacteria in Germany until after World War II.

In the United States, research on microorganisms was carried out in wide range of institutional settings and for a variety of reasons. In 1899, a group of microbiologists and bacteriologists founded the Society of American Bacteriologists (hereafter "SAB"). The program of the first meeting of the SAB illustrates the range of interests included in the organizations. Practical problems predominated. Twenty-one of twenty-six papers concerned medicine, agriculture, water supplies and sewage, and food preservation. In contrast, H.W. Conn, Professor of Biology at Wesleyan University, gave a paper that was distinctly general in character: "The Natural Varieties of Bacteria." Conn's second paper, however, revealed a different concern: "Certain Practical Applications of Bacteriology to Dairying." The topics discussed at the second meeting of the Society were even more utilitarian in character.⁽²⁵⁾

Historian Patricia Gossel has argued that the urgent necessity to standardize methods and techniques motivated bacteriologists to organize a society.⁽²⁶⁾ In the words of the first president of the SAB, "The really distinguishing characteristic of bacteriology is not merely its subject matter but its methods, not so much the peculiar organisms with which it deals -- interesting and important these are -- as the peculiar means it has devised and employed for studying these organisms."⁽²⁷⁾ Bacteriologists defined themselves as a coherent group on the basis of common methods and techniques, not in terms of a shared body of knowledge or research interests.

While practical problems predominated in the early SAB, many bacteriologists preserved a strong interest in theoretical questions. Beginning in the late nineteenth century, a succession of American bacteriologists claimed that their field was a "biological science." The first president of the Society, W.T. Sedgwick, studied general biology at Yale and became a close friend of embryologist E.B. Wilson. Sedgwick considered both basic and applied aspects of bacteriology in his Presidential address.⁽²⁸⁾ In practice, however, institutional and career opportunities in the various branches of applied microbiology created a constant diversion of personnel and research efforts. Sedgwick spent most of his career building programs in public health at MIT and Harvard. Theoretical research, however, could be undertaken within these institutions, even if it were secondary to the main interests. Utilitarian concerns competed for the attention of researchers and diverted the efforts of many scientists from their theoretical interests to practical problems. At the same time, these concerns provided opportunities for fundamental studies.

By the beginning of the twentieth century, the applied fields of microbiology and bacteriology provided a more rapidly increasing supply of institutional positions than did the theoretical fields. In only a few locations were strong theoretical programs sustainable. Opportunities for applied work exceeded those for fundamental research. Research on microorganisms was conducted in a wide array of institutions, including hospitals, public health departments, breweries, and agricultural stations. Some research on microorganisms was carried out in universities within traditional academic disciplines such as zoology and botany. In some settings, this research was called microbiology; in others, bacteriology. This institutional diversity and linguistic instability, which persisted well into the twentieth century, imply that bacteriology had not attained the social or intellectual coherence characteristic of organized disciplines. The diverse range of "service roles" that supported the study of microorganisms ensured that there would be many kinds of bacteriology or microbiology.⁽²⁹⁾ This diversity may have made the consolidation of a discipline of bacteriology impossible.

One might argue that medical bacteriology achieved something like disciplinary status by the early twentieth century. For other branches of microbiology and bacteriology, this appears doubtful. In aggregate, bacteriology and microbiology were comprised of a collection of diverse research orientations. Conceptualizing general microbiology as a research orientation can help explain how and why it occupied niches in diverse kinds of locations, including biology departments, agricultural research stations, marine biological laboratories, and even schools of engineering. For general microbiology, colonizing disciplines may not have been a strategy consciously adopted by leaders, but a consequence of institutional realities.

C. A Laboratory for Microbiology at Delft

One of the first sustained research programs in general microbiology developed in the chemical engineering faculty of the Polytechnische School in Delft, the Netherlands. Founded in 1895, the Laboratory for Microbiology at Delft exemplifies how programs in general microbiology came to occupy unlikely institutional niches. The social and economic justifications for the laboratory's existence were that scientific research would eventually produce useful results. Its practitioners, however, took advantage of this institutional space to advance their own theoretical projects. The ideal of pure science, articulated in the late nineteenth century, proved to be a strategically useful concept for preserving a degree of autonomy for theoretical studies.

Dutch society discovered "science" in the first half of the nineteenth century. Especially after the Napoleonic period, Dutch political leaders, industrialists, and scholars who shared a liberal-progressive viewpoint sounded various kinds of calls for science to lead the reform of Dutch society. There were many meanings of science and a variety of expectations for its capacities. In the 1830's, as historian Bert Theunissen has shown, a group of scholars at the University of Utrecht argued that the traditional university curriculum centered on the classical languages and literature was obsolete, no longer appropriate for a modernizing nation. Espousing a mixture of positivism and various Enlightenment philosophies, these scholars argued that science provided the proper basis for material and spiritual progress of Dutch society. For these scholars, science meant primarily scientific reasoning. They recommended education in inductive reasoning and scientific analysis for all of society's leaders, from industrialists to lawyers.⁽³⁰⁾

These wide-ranging debates in conjunction with practical concerns stimulated a call for the reform of engineering, an endeavor which has a singular importance in the Netherlands. Without it, most of the country would be under water. Effective pumps, canals, dikes and floodgates were necessary for the physical existence of the Netherlands. Until the nineteenth century, the crucial work of water management was carried out by neighboring communities, according to local custom, tradition, and experience. In the 1830's and 1840's, industrialists and political leaders argued that custom and tradition were no longer adequate to secure the physical or political integrity of the country. They called for the state to establish an institute where engineering could be developed on the basis of scientific principles, and where engineers could be formally trained. The Ecole Polytechnique in Paris provided a model institution for these reformers.⁽³¹⁾

Their arguments were successful and, in 1842, the Koninklijke Academie (Royal Academy) was founded by royal decree in the town of Delft. Mandated to train civilian engineers for government, industry and commerce, the Academy instituted formal training in the major branches of engineering. In 1863, this institution was reorganized and renamed the Polytechnische School. Reorganized again in 1905, it became the Technische Hoogeschoole in Delft, informally called the "THD." The name and basic administrative structure of the THD remained unchanged until 1987, when it was given full university status, and became the Technische Universiteit Delft (Delft University of Technology).⁽³²⁾ It remains the most prestigious school of engineering in the Netherlands.

In the nineteenth century, the THD occupied an intermediate position in Dutch higher education. While emphatically not a "true" university, it was nonetheless recognized as an institution of higher learning. Its faculty and students strove with some success for the status and privileges of the traditional universities. The faculty won the right to be called "professors," and students emulated their university counterparts in establishing rituals, revels, and pageants. Most importantly, a policy of "free study" was adopted at Delft, as at the universities. Students were allowed to take any courses that they chose; their degrees would be awarded on the basis of examinations only.⁽³³⁾

From the beginning, the basic sciences had a prominent place in the training of Dutch engineers. Many of the THD faculty, especially in the first generation, had taken degrees in the traditional universities. In the 1890's especially, the THD (then still called the Polytechnische School) had considerable space in its curriculum and culture for academic subjects and values. At the same time, many of the students who attended the THD were from the commercial middle and lower classes, and would have been excluded from the traditional universities. The THD provided an avenue for social mobility that was rare in Dutch society. In the twentieth century, as engineering became an established and respected profession in the Netherlands, the THD attracted increasing numbers of students from upper middle class families.⁽³⁴⁾

As historian Bert Theunissen has discussed, the ideal of "research" became a new element in the debates about the proper relationship between science and society in the Netherlands in the late nineteenth century. The botanist Hugo de Vries became a leading spokesman in the Netherlands for the value of scientific research. De Vries vigorously promoted both "pure" and "practical" research, while making a sharp distinction between them. Practical research, he argued, was essential for social and economic progress, because it could make direct contributions to the basic needs of society, especially in agriculture and horticulture. It merited, therefore, government support and private investment. He promoted pure research with even more enthusiasm, advancing three arguments on its behalf. First, pure research was essential for discovering fundamental laws. Second, it provided the basis for sound practice. Third, de Vries held, the practice of pure research advanced the spiritual improvement of mankind.⁽³⁵⁾

The arguments made by de Vries resemble discussions held in the U.S. at about the same time. As historian Ronald Kline and others have shown, the terms "pure" and "applied" science became prominent features in the public rhetoric of American scientists and engineers in the 1880's. Kline has argued that the construction of these categories served the interests of both scientists and engineers, simultaneously engaged in the process of professionalization. Scientists and engineers used these concepts to define distinct but complementary social roles. By construing their work as "applied science," engineers could associate themselves with the prestige of science, while carrying out work of practical value. The concept "pure science" allowed scientists to stake out a terrain of work unconstrained by practical demands. At the same time, the concept "applied science" carried the convenient implication that "pure science" provided the basis for practical work, and was of direct value to society.⁽³⁶⁾

As historian George H. Daniels has pointed out, scientists in the United States articulated and adopted the ideal of pure science only after the practical utility of science was no longer in doubt.⁽³⁷⁾ One could argue that the ideal of pure science was necessary precisely because the increasing usefulness of science threatened the status and autonomy of scientists as scholars. Researchers adopted the ideal of pure science to protect an ideal of scholarship as a cultural force.

In general, increasing confidence in the usefulness of science led to new investment in institutions for scientific training and research. Technical schools, universities, and commercial enterprises formed new relationships in the Netherlands, as in other industrial countries. Scientists committed to fundamental research took advantage of these opportunities in a variety of ways. For some, industrial positions provided training in research, access to facilities, and the opportunity to encounter problems that could be translated into theoretical questions.

In some cases, industrial enterprises established fundamental research laboratories. In 1847, for example, the Danish brewer J. C. Jacobsen founded the Carlsberg Brewery near Copenhagen with the aim of making the best beer in the world. To achieve his goal, Jacobsen turned first to German yeasts and then to French science. With yeasts obtained in Munich and Hamburg, Jacobsen successfully produced high quality beer, but only some of the time. Production was especially unreliable in summer, when frequent spoiled batches had to be discarded. After learning about Pasteur's work, Jacobsen concluded that a scientific laboratory would be a valuable asset for the brewery. In 1871, he installed a small laboratory in the brewery to carry out research on malting, brewing, and fermentation. In 1876, he established the Carlsberg Foundation with an expanded research mission. Jacobsen supported scientific research for both its practical and cultural value. He specified that the results of the new laboratory should not be kept secret. The Carlsberg Laboratory provided a niche for the pursuit of both practical and general microbiological research.⁽³⁸⁾

J.C. van Marken, the owner of a successful yeast and alcohol factory in Delft shared Jacobsen's interest in both fundamental and practical science. A friend of Hugo de Vries, van Marken had become captivated by the arguments that science could improve both society and industry. In the 1880's, van Marken attempted to organize his factory and workers on a "scientific basis." With a greater likelihood of success, he turned to science to solve the problem of contamination of yeast cultures in the factory. Like Jacobsen in Carlsberg, van Marken decided to establish a research laboratory for the factory. In 1885, he set up the first industrial research laboratory in the Netherlands. On the advice of de Vries, van Marken hired M.W. Beijerinck (1851-1931) as his first director of research.⁽³⁹⁾

In many respects, Beijerinck was an unlikely candidate for the position at the yeast factory. In 1885, he was a teacher at a Dutch agricultural college. He had no experience in industry and little with microorganisms. On the other hand, he had a demonstrated talent for research. Beijerinck had attended the THD for financial reasons: he could not afford a university education. Once he had graduated and was employed, however, he was able to attend the University of Leiden on a part-time basis. There he studied botany, his first love, and wrote an outstanding dissertation in 1877 on the formation of plant galls. His position at the agricultural college allowed him to continue research and he conducted many experiments on the hybridization of grains. Beijerinck was deeply fascinated by the great biological problems of the period, especially evolution and heredity. His research focused on abnormal growth, as a means to understanding general problems in physiology. Throughout his scientific life, Beijerinck endeavored to transform practical problems into fundamental research questions. He took advantage of each of his institutional opportunities to pursue theoretical research.

The position at van Marken's factory was attractive to Beijerinck precisely because it offered better conditions for research than were available at the agricultural college. The scientist was given a new laboratory, a relatively high salary, and considerable freedom in choosing his research topics. Before assuming his position at Delft, Beijerinck visited several laboratories to learn basic microbiological technique. His first stop was the laboratory of de Bary, the leading specialist in mycology, at the University of Strasbourg. Despite his relative ignorance, Beijerinck reputedly annoyed de Bary by pointing out his errors with great vehemence. He also paid a visit to the laboratory founded by Jacobsen in Copenhagen, but later complained that he had learned nothing important. After that experience, he canceled a projected visit to Koch's laboratory, on the grounds that is would not be worthwhile. Beijerinck consistently displayed hostility toward medical bacteriology.⁽⁴⁰⁾

In September 1885, Beijerinck began working at the yeast factory. He remained for a decade. During that period, he manage to conduct a wide range of fundamental research in addition to the practical work required by his position. For the first two years, his fundamental research largely concerned botanical subjects. He published a series of important papers on plant galls, root formation, and root diseases. His position, however, obliged him to pay some attention to problems of fermentation and, hence, the physiology of microorganisms. He turned his attention to a wide range of microbiological problems, and made several fundamental contributions.

Combining long-standing botanical interests with his new expertise in microbiology, Beijerinck investigated the formation of root nodules in the Leguminosae, the invaluable family of peas and beans. These plants have the capacity to grow in and enrich nitrogen-poor soil. It was known that some factor in the root nodules of these plants allowed them to convert atmospheric nitrogen into a biologically usable form, a process called "nitrogen fixation." Beijerinck determined that a previously unknown species of bacteria, which he named Bacillus radiciola, carried out the critical process of nitrogen fixation.⁽⁴¹⁾ This research won Beijerinck an international reputation among botanists and agriculturalists.

In other microbiological projects, he studied the physiology of luminous bacteria, the isolation and culturing of green algae, and the symbiotic relationships between algae and fungi in lichens. Only occasionally did he carry out projects with direct practical relevance to the yeast factory. He studied the production of butyl alcohol by fermentation, the physiology of microorganisms in yogurt and kefir, and discovered a new species of yeast, Schizosaccharomyces octosporus.

Despite its considerable intellectual value, Beijerinck's research brought no financial benefit to his employer. For the most part, the industrialist van Marken was remarkably tolerant of Beijerinck's wide-ranging research activities. Nonetheless, it became evident that all concerned might be happier if a more appropriate research position could be found for Beijerinck. With the support of other industrialists, van Marken successfully lobbied for the establishment of a laboratory and professorship in microbiology within the faculty of chemical engineering at the nearby Polytechnische School.⁽⁴²⁾

In 1895, Beijerinck became the first professor of the new Laboratory for Microbiology in Delft. His position and institutional arrangements were unusual if not unique. In the 1890's, there was considerable tolerance of academic research at the technical school, especially in the chemical engineering faculty. Beijerinck was free to develop microbiology as he saw fit. He remained true to his background as a botanist and defined microbiology as a general science of life. Beijerinck's inaugural address, "Biological Science and Bacteriology," expressed this basic outlook.⁽⁴³⁾ He expected research on microorganisms to address major issues in the life sciences: heredity, evolution, variability, the nature of growth, and development.⁽⁴⁴⁾

Beijerinck took full advantage of the opportunities afforded by his new position to conduct theoretical research. From 1895 until his retirement in 1921, Beijerinck produced research at a prodigious rate. Most of it had little obvious practical relevance. Although he sat on a few governmental advisory boards, he made no serious effort to sustain his links to industry. There seems to have been little pressure on him to do so, as his growing reputation reflected well upon the THD. Under Beijerinck's influence, the THD became home to a strong program of fundamental research in microbiology. His abiding interests in heredity and evolution provided the intellectual context for his research on microbiological topics until his retirement in 1921.⁽⁴⁵⁾

Beijerinck's experience in the yeast factory provided him with numerous questions he could translate into fundamental research problems. While working on industrial fermentations, Beirjerinck encountered many organisms that had either desirable or undesirable effects on the process at issue. Bacteria that produced lactic acid, for example, were frequent contaminants of yeast production. At the THD, Beijerinck translated this problem into a general study of bacterial physiology and phylogeny. He carefully isolated a variety of species of lactic acid bacteria and systematically studied the conditions under which they produce various organic acids. He determined that some, but not all, bacteria that produce lactic acid constituted a natural group. The organisms in this group shared a set of characteristics: complete immotility, the absence of the enzyme catalase, absence of the capacity to form spores, and various biochemical properties. He proposed to give this group the rank of genus, with the name Lactobacillus. He argued that those species of bacteria capable of producing lactic acid but lacking the other common characteristics belong to a different genus.⁽⁴⁶⁾

Similarly, Beijerinck systematically investigated the butyl alcohol or butyric acid bacteria, and the acetic acid bacteria, two more groups of organisms he first encountered at the factory. Again, he studied the biochemical and morphological properties of several species in exhaustive detail in order to determine which group of species formed a natural group.⁽⁴⁷⁾

Beijerinck's investigation of the "mosaic disease" of tobacco plants illustrates his talent for exploiting practical problems for theoretical ends. This project led to one of his most important conributions, the formulation of a concept of viruses as a distinct biological category. Beijerinck first learned of the infectious nature of the tobacco mosaic disease while teaching at an Agricultural School in 1885. He made an attempt to isolate a causative agent, but did not succeed. He tried again two years later, while employed at the yeast factory, but again failed, despite his greater experience with bacteriological methods. Finally, after his appointment to the laboratory in Delft, he had both the experience and the institutional support to give the problem sustained and systematic attention. By 1897, he had experimental evidence that the "contagious principle" was not a microscopic organism, though it shared several characteristics with living things. Beijerinck called the infectious principle: "contagium vivum fluidum." He conceived of this principle as a distinct kind of entity, neither organismal nor molecular.⁽⁴⁸⁾ Beijerinck's concept of the virus was much discussed in ensuing debates in the twentieth century over the nature of these entities. On the basis of this and related work, Beijerinck was retrospectively awarded the title "founder of virology."⁽⁴⁹⁾

Beijerinck set out to explore the vast world of non-pathogenic bacteria, and to investigate their role in the cycles of nature. For this purpose, he relied an important technique variously known as the "accumulation method" or the "elective" or "enrichment culture method," initially developed by the Russian scientist Sergei Winogradsky. Based on ecological reasoning, this procedure could be used to obtain strains of bacteria or other microorganisms from their natural environments. Beijerinck elevated this method into a powerful instrument of research and a principle of biological reasoning. In this technique, a sample of soil, water, or ill-defined slime from an environment of interest is incubated in a well-defined test medium, in which some organisms would be able to grow more rapidly than others, and would thereby be enriched in the culture. In practice, this approach was extremely useful in preparing cultures of many different kinds of microorganisms, isolated from a variety of natural environments. It made it possible to isolate relatively easily an organism that occurred only very rarely in a given place, and greatly expanded the known range of bacterial diversity.

Beijerinck considered the systematic application of the elective culture technique to be an essential part of a biological approach to microbiology:

This approach can be concisely stated as the study of microbial ecology, i.e. of the relation between environmental conditions and the special forms of life corresponding to them....This is the most necessary and fruitful direction to guide us in organizing our knowledge about that part of nature which deals with the lowest limits of the organic world, and which constantly keeps before our mind the profound problem of the origin of life.⁽⁵⁰⁾

Beijerinck employed the enrichment culture technique especially frequently during the period from 1900 to 1910. During that time, he brought into the laboratory numerous strains of bacteria from many different environments. The procedure was gradually absorbed into the set of standard techniques commonly available to microbiologists.

Beijerinck's considerable experience with the enrichment culture method and his broad biological interests provided the background for what became one of his most famous accomplishments, the isolation from soil of a strain of free-living bacteria capable of transforming atmospheric nitrogen into a biologically useful form. He thus identified the source of "fixed-nitrogen" in arable soils, a question of both great practical and theoretical interest. In 1901, he successfully isolated an organism with these capacities, which he named Azotobacter.⁽⁵¹⁾

Beijerinck's project ran counter to one of the major currents of late nineteenth century science, the rapid and dramatic emergence of medical bacteriology. Dramatic discoveries of the bacterial agents responsible for major infectious diseases were announced almost annually from 1876 through the 1890's. From the perspective developed by Beijerinck and his students, pathogenic bacteria represented only a small fraction of the microbial world. From a broad biological viewpoint, pathogens were neither especially interesting nor important.

At Delft, Beijerinck established the basic institutional structures and intellectual culture for a program in microbiological research. Difficult to get along with and given to fits of depression, Beijerinck was never a popular teacher. Nonetheless, he trained several talented assistants who worked under his direction for several years at a time. He secured a place for his subject in the curriculum. Between 1898 and 1921, eight doctoral theses were prepared wholly or largely under Beijerinck's direction. He and his assistants occupied laboratory space, purchased microscopes and other bacteriological equipment, and established an enormous culture collection of microorganisms. He established a model for the practice of microbiology as a biological science.

Beijerinck's career illustrates the kind of research path made possible by the developing links among industrial, technical, and academic institutions stimulated by the expectation that scientific research would have practical value. Beijerinck's migration through several different kinds of Dutch scientific institutions and an industrial concern produced an unanticipated result. His training at the THD allowed him to support himself while he pursued a doctorate in botany at a major university. A position as an industrial researcher was responsible for converting him from the study of botany to microbiology. Because microbiology in principle could have industrial relevance, a technical school could legitimately provide an institutional base for research in that subject. Because the THD accommodated a large measure of fundamental research, especially in the chemical engineering faculty in the 1890's, it was possible for Beijerinck to establish a strong program in basic microbiology.⁽⁵²⁾ The result of this set of events was one of the first sustained programs in the world in which microbial physiology and ecology were at center stage. Beijerinck's distinctive program in microbiology could be established at the THD because industrial, academic, and technical research were not fixed categories separated by impermeable institutional boundaries. Rather, these categories and institutions were (and continue to be) engaged in a process of definition and redefinition in relation to one another.

Despite his achievements and the considerable recognition he won, Beijerinck expressed regret that he had become a microbiologist. Otherwise, he lamented, he would have discovered both Mendel's laws and cell-free fermentation, i.e. two of the most important developments of nineteenth century biology.⁽⁵³⁾

D. Microorganisms and Grand Ambitions

Beijerinck was an esteemed if unpopular member of the faculty of the THD when van Niel began his studies there in 1916. At the time, van Niel had no special interest in microbiology and probably knew little about it. He entered the THD with the intention of becoming an industrial chemist. In many ways, he was a typical student, a member of the commercial middle class who might not have found a way to an academic university. He took advantage of the opportunity to demonstrate his scientific talent within the first term. He was able to complete a laboratory course in qualitative analysis in less than a third of the time taken by most students.⁽⁵⁴⁾

This promising beginning was soon interrupted. In January 1917, van Niel was inducted into the Dutch army. Though spared the horrors experienced by many combatants in the first World War as the Netherlands remained neutral, van Niel found his wartime experience "shattering." Many of the basic tenets of his life were undermined during his year in the army. He was frequently repulsed by what he perceived to be the frequent arbitrary and illogical exercise of military authority. For the first time in his life, he made several friends who were seriously interested in intellectual matters. Through them, he discovered a love for art, literature, and philosophy. He spent much of his military service reading literature, especially existentialist writers of the nineteenth century. The result was further erosion of his faith in Calvinism and the previous sources of authority in his life. He came to see that what he had believed in the past "rested on a shaky foundation." These new doubts initiated a "rebellious period" that lasted several years.⁽⁵⁵⁾

When van Niel returned to the THD in 1919, his mental outlook "had undergone radical changes," he wrote many years later.⁽⁵⁶⁾ Still fascinated by literature and disillusioned by the world as it was, he considered abandoning chemistry to become a writer. A trusted family member intervened and convinced van Niel on practical grounds to complete his degree in chemical engineering. Resuming his studies, van Niel took several courses with G. van Iterson, who had taken his degree at the THD under Beijerinck. Van Niel studied plant anatomy, technical botany, genetics, and the chemistry and technology of wood and plant and animal fibers. At the same time, he continued his broad reading of literature. During the academic year 1920 to 1921, van Niel was introduced to microbiology through Beijerinck's courses. Van Niel later wrote that the lectures whetted his appetite for microbiology. Still, at the end of 1921, he had not settled on microbiology as the subject for his final year of specialized study.⁽⁵⁷⁾ One obstacle was the uncertainty of the future of the Laboratory of Microbiology.

In 1921, at age seventy, Beijerinck was forced by Dutch law to retire. With considerable grumbling and some bitterness, the great scientist removed to his country residence and never set foot in Delft again.⁽⁵⁸⁾ Choosing a successor for the eminent figure was no easy task. The surprising choice was Albert Jan Kluyver (1888-1956), a graduate of the THD with many promising qualities but no special expertise in microbiology.

The strength of Kluyver's training lay in chemistry and technical botany. He obtained his undergraduate degree in Chemical Engineering in 1910 and then spent a summer studying with Hans Molisch at the Plant-Physiological Institute at the University of Vienna. Kluyver returned to Delft to prepare a doctorate under the direction of van Iterson, then professor of Microscopical Anatomy. After obtaining his degree in Technical Science in 1914, Kluyver spent next five years in the Dutch East Indies as a technical consultant with the Department of Agriculture, Industry, and Commerce.⁽⁵⁹⁾

When Kluyver assumed the chair in microbiology, his knowledge of microbiology was minimal. Two capable assistants inherited from Beijerinck provided Kluyver with an invaluable reservoir of expertise. They also ensured a degree of continuity from Beijerinck's program of research to Kluyver's. On a few occasions, Kluyver visited Beijerinck in his country home to consult with him. The core of Kluyver's interests, however, differed from those of Beijerinck. Kluyver was chiefly concerned with biochemical transformations and the energetics of metabolism whereas heredity and evolution were the central theoretical interests underlying Beijerinck's research. In private, Beijerinck looked down upon Kluyver for being a chemist and not a biologist.⁽⁶⁰⁾ Kluyver, on the other hand, was skeptical of studies of microbial heredity, which he considered to be confused and non-rigorous in the 1920's.⁽⁶¹⁾ Further, analysis of the chemical activities of microorganisms may have been seen as more appropriate for a laboratory in a chemical engineering faculty than the study of heredity and evolution. By the 1920's, the THD was less tolerant of academic research than it had been in the 1890's. Kluyver modified the focus of the laboratory's research in response to his own interests, changing institutional demands, and the pressure of more general economic conditions.

Kluyver did not abandon fundamental research, however. Rather, he developed a lively and productive program of research in which the practical and the fundamental were pursued as harmonious complements. Kluyver announced his intentions to pursue both practical and fundamental research in his inaugural professorial address in 1922: "Instruction at the present-day Technical University has gradually expanded into a grand symphony of pure and applied research."⁽⁶²⁾ As he continued, he took full advantage of the argument that fundamental studies provide the basis for practical applications.

Kluyver began by emphasizing the potential importance of microbiology for industry. To that end, Kluyver raised the specter of the exhaustion of fossil fuels, a widespread concern in the 1920's.⁽⁶³⁾ He pointed out that declining petroleum stocks meant rising prices for organic derivatives used in the chemical industry. Kluyver postulated that industrial microbiology would be critical for filling the expected shortfall in organic chemicals. He pointed out that microorganisms could easily transform a simple molecule like glucose into a variety of organic compounds important for industry. As examples, he cited the production of alcohols by yeasts, the synthesis of butanol, acetone, butyric acid, and dihydroxyacetone by bacteria, and the formation of citric acid and fumaric acid by molds. Taking another angle, he noted that microbiological knowledge could be invaluable in industries where microbial contamination interfered with production.⁽⁶⁴⁾

Kluyver made clear that he intended to reserve an important place for fundamental studies in his program. He praised his predecessor's distinguished research and noted that the study of "theoretical" bacteriology was restricted to only a few locations, of which Delft was one of the most prominent. He argued that "theoretical" bacteriology was important for two reasons: for its own sake and as the basis for progress in applied work. "Once more," he concluded, "shall I express my profound feeling of responsibility towards microbiology not only as a subject...but as a science."⁽⁶⁵⁾

Kluyver's rhetoric translated into practice. As historian Olga Amsterdamska has shown, Kluyver proved to be a genius at arranging his laboratory's activities so as to pursue both fundamental and practical research on a high level.⁽⁶⁶⁾

Initially, Kluyver was occupied with mastering the field of microbiology. In the first two years of his professorship, Kluyver set out to survey the broad area of microbial metabolism. Both practical and theoretical questions motivated his work. Knowledge about the chemical activities of microorganisms was scattered among many sub-fields and disciplines. The chaotic state of knowledge about microbial metabolism reflected the institutional diversity and disciplinary incoherence of microbiology. Kluyver worked assiduously to assemble the many scattered and disconnected observations on the chemical activities of microorganisms. In the process, he kept a sharp lookout for processes that could be useful in industry. Simultaneously, he was motivated by theoretical questions. Kluyver sought to identify common patterns amid the diverse reactions carried out by microorganisms. Ultimately, Kluyver hoped to discover unifying principles of microbial metabolism.

Kluyver was quick to seize upon theoretical questions that arose during investigations of practical processes. The study of the souring of beer, for example, led Kluyver to important theoretical insights. A standard exercise in Kluyver's laboratory course was to isolate vinegar bacteria from beer left out in the air to sour. In 1923, one of Kluyver's students conducted this exercise and found a bacterium with unusual properties. A typical vinegar bacterium oxidized its initial substrate to acetic acid. In comparison, this new strain carried out an incomplete oxidation; it stopped a few steps prior to producing acetic acid.⁽⁶⁷⁾ Kluyver named this organism Acetobacter suboxydans.

Kluyver found that various strains of Acetobacter differed in the extent to which they oxidized substrates. He recognized that these strains could be arranged in a series, such that the metabolic end-product of one strain could serve as the oxidizable substrate for the next. The construction of such series brought a new kind of order into the study of microbial metabolism. Kluyver coined the phrase "comparative biochemistry" to refer to the process of making systematic comparisons of the detailed biochemical metabolism of microorganisms.⁽⁶⁸⁾ Kluyver concluded that broad surveys and systematic analysis of microbial metabolism had more to offer than information useful to industry. He perceived that comprehending the diversity of microbial metabolism could lead to the most comprehensive unifying principles in biochemistry. One of his first papers on microbiology, published in 1924, announced this viewpoint. Reflecting his interest in general principles, the paper was called "Unity and Diversity in the Metabolism of Microorganisms."⁽⁶⁹⁾

In the next few years, Kluyver expanded on this theme. He attempted to identify a small set of biochemical sub-reactions common to all fermentation processes. Ultimately, he found four simple reaction types from which all known fermentation processes could be composed. These were:

1. The splitting of a hexose molecule into two trioses;

2. The transformation of the triose into acetaldehyde plus either lactic acid or formic acid;

3. The dehydrogenation of formic acid and acetaldehyde;

4. The condensation of acetaldehyde to either acetyl methyl carbinol or butyric acid; and the rearrangement of acetic acid ultimately to acetone and carbon dioxide.

Kluyver also showed that the different outcomes in these fermentation processes could be traced to the fate of three key intermediates: triose, pyruvic acid, and acetaldehyde.

Like most of Kluyver's work, this theory had practical and theoretical implications. It was important for biochemical theory because it revealed fundamental similarities and interrelations among diverse fermentations. This knowledge was also potentially valuable for industry because it implied that manipulating culture conditions could direct fermentation reactions to produce products of commercial interest.⁽⁷⁰⁾

By 1926, Kluyver was ready to make a bid to establish himself as a leading theorist of biochemistry. That year, Kluyver and his assistant, H.J.L. Donker, proposed a new general theory of metabolism aimed at nothing less than the unification of biochemistry. Kluyver's intellectual ambition to unify biochemistry, if realized, would admit him the company of elite European scientists. Perhaps as ancient as philosophy, the ideal of "unity" was resonant in a variety of scientific contexts in the 1920's. To some physicists, for example, the unity of physics was under siege in the 1920's by the uncertain implications of the quantum revolution.⁽⁷¹⁾ In Vienna, the "unity of science" movement was underway.⁽⁷²⁾ Among American biologists, the "unity of life" became a new principle guiding research directions in 1920's.⁽⁷³⁾ F.G. Hopkins, a leading biochemist at Cambridge University, incorporated the ideal of unity at several different levels in his program in "dynamic biochemistry."⁽⁷⁴⁾

In developing a unified theory of biochemistry, Kluyver entered intellectual terrain dominated by Hopkins and Otto Warburg, the director of the Kaiser Wilhelm Institute for Experimental Biology in Berlin. Kluyver's approach to biochemistry relied on the perspectives developed by the German chemist Heinrich Wieland, a scientific opponent of Warburg. In 1913, Wieland proposed that the oxidation of ethanol to acetic acid, for example, resulted from the transfer of hydrogen from the alcohol molecule to an acceptor molecule that need not be oxygen. Wieland then proposed that all biological oxidations could occur as dehydrogenation reactions. Warburg, who deemed it obvious that oxidations must involve oxygen, heatedly opposed this theory.⁽⁷⁵⁾

Taking Wieland's side, Kluyver attempted to make dehydrogenation reactions the basis of all of metabolism. In "Die Einheit in der Biochemie," published in 1926, Kluyver and Donker proposed that apparently complex biochemical processes were simply the net result of sequential hydrogen transfer reactions. They proposed that all biosynthetic processes were composed of four types of simple step reactions:

1. AH + B A + BH

2. AH-B A-BH

3. AH-B A + BH

4. AH + B A-BH

Kluyver obtained the evidence for this proposition from the analysis of diverse bacterial and fungal fermentations.

Kluyver's ambitious and plausible attempt to unify biochemistry attracted considerable attention. In 1930, he was invited to speak at the University of London about his theory of metabolism. Kluyver took the opportunity to promote both the utility of microorganisms as experimental material and the value of the approach he called comparative biochemistry:

Although this line of study has not as yet been much developed, it may in future win the same significance for biochemistry as "comparative anatomy" has already long ago attained for anatomy.⁽⁷⁶⁾

The concept of comparative biochemistry implied that research on microorganisms could be relevant to the study of all living things. It was a way of elevating and widening the importance of microbiology. Kluyver compared his approach to biochemistry to the research at Cambridge carried out under Hopkins' direction:

Whilst most of your countrymen have concentrated their efforts on the study of the inner mechanism of a clearly defined biochemical reaction, we have attempted to obtain a more general survey of the field of microbiological biochemistry, which at first sight appears so chaotic.⁽⁷⁷⁾

Kluyver then surveyed the innumerable biochemical reactions that could be understood as the transfer of hydrogen atoms from a donor to an acceptor compound.

In these lectures, Kluyver addressed the question whether reactions carried out by living things were the same as or different from those occurring in the test tube. Was there a difference between "vital" and "enzymatic" processes? Kluyver believed that his unified theory of biochemistry resolved the matter: "So we are forced to conclude that a difference between an enzymatic and vital part of biochemistry is untenable."⁽⁷⁸⁾

Kluyver was not a radical reductionist, however. His viewpoint can be characterized as what historian Garland Allen has called "holistic materialism."⁽⁷⁹⁾ Kluyver believed that the integration of biochemical reactions required the activity of the intact cell. He expressed the point in his lectures:

I have only to remind you how the conversion of sugar into fat demands for its successful completion a harmonious succession of a special set of primary reactions out of the many that are possible. And the perfect harmony which is the one condition for such a long chain of reactions is the exclusive perogative of the living cell.⁽⁸⁰⁾

Much of the evidence for Kluyver's theoretical work derived from research projects carried out by his students. For dissertation projects, Kluyver typically assigned his students to carry out systematic investigations of limited groups of bacteria that had some potential practical relevance. This policy tended to ensure that students would undertake projects that were both feasible and attractive to potential employers. At the same time, Kluyver could integrate the results of these more focused investigations into his general theoretical constructions.⁽⁸¹⁾

Kluyver was keenly aware that the best employment possibilities for his students lay in industry, agriculture, and government. In the depressed economy of the 1920's and 1930's, these positions were not easy to obtain. Kluyver worked hard to make contact with Dutch enterprises for which microbiological research could be useful. He renewed contact with the nearby Yeast and Spirits Factory in Delft and established cordial relations with many other companies. Many of Kluyver's students found employment in breweries, the dairy industry, sugar factories, water purification and sewage treatment plants, food preservation industries, and Royal Dutch Shell's chemical laboratory.⁽⁸²⁾

The institutional interdependence of theoretical and practical research meant that two different contexts for understanding the meaning and purpose of microbiological work were available at the Laboratory for Microbiology at Delft. Microbiological research could be understood either as fundamentally practical in nature, aimed at developing technical industrial procedures, or as a theoretical project, directed toward discovering general and fundamental scientific principles about life phenomena. Kluyver proved to be a talented conductor of the "symphony" of pure and applied research. Under his direction, they proceeded in harmony for nearly four decades.

E. High Ideals and Local Constraints

When Kluyver delivered his inaugural professorial lecture, van Niel was among the curious students in the audience. On the basis of that lecture, he decided to specialize in microbiology for his last year at the THD. Many years later, van Niel admitted that the spirit of the lecturer impressed him more than the substance of the lecture. He chose microbiology in order to study with Kluyver.

Van Niel joined the Laboratory for Microbiology in 1922 just as Kluyver began his grand and ambitious program. Van Niel's first microbiological investigations were mundane in comparison. His first project was to determine how long a culture of yeast could survive under conditions that sustained normal metabolic activity but did not permit cell multiplication. Unfortunately, van Niel could not find such conditions. In any growth medium in which they could live, the yeast cells multiplied, albeit sometimes at a slow rate. As his second project, Van Niel tried to prepare pure cultures of the bacterium Bacillus calfactor, organisms that generate heat in moist hay. After many frustrating failures, he succeeded, and was then able to stain the flagella of these organisms. These studies fulfilled the last requirement for the degree in chemical engineering, which van Niel received in 1923.⁽⁸³⁾

Despite the poor employment prospects for graduates of the THD, van Niel had made no plans for the future. To his great good fortune, a position as Kluyver's assistant became available that year. In this capacity, van Niel was responsible for maintaining a large collection of bacteria, yeasts, algae, and protozoa, and for preparing demonstration materials for Kluyver's courses in general and applied microbiology, given in alternate years. Through this work, van Niel gained substantial experience handling a wide range of microorganisms.⁽⁸⁴⁾

Like Beijerinck and Kluyver, van Niel was disposed to draw fundamental problems from the sludge of applied work. In 1923, van Niel was charged with preparing demonstration material for Kluyver's course on the microbiology of water and sewage. As expected, he successfully isolated several species of iron and sulfur bacteria. In the course of this work, van Niel became enamored with a group of bacteria that he found exceptionally intriguing and beautiful, the Thiorhodaceae, or purple bacteria. It was, in a way, love at first sight. True to their name, the bacterial cultures were beautifully red and purple in color.

Even more attractive to van Niel was the mystery of their metabolism. In reading about previous studies on the purple bacteria, van Niel learned that there were conflicting interpretations of their biochemistry. It was unclear if they were "chemosynthetic," "photosynthetic," or both. Van Niel undertook some preliminary experiments. By 1926, van Niel had evidence that purple sulfur bacteria were photosynthetic, an important discovery if correct. They were, van Niel thought, perfect subjects for a dissertation.⁽⁸⁵⁾ Kluyver, however, did not agree. Like the other students in Delft, van Niel was subject to Kluyver's policy of preparing students to work in industry. Under pressure from Kluyver, van Niel very reluctantly agreed to give up his newly-beloved purple bacteria for a more practical topic.

The selection of van Niel's dissertation topic was typical of Kluyver's skillful way of identifying research problems that had both practical relevance and theoretical interest. Always on the alert for such problems, Kluyver took careful note of an article published in 1923, which pointed out that propionic acid could be useful in industry either as a solvent or as a precursor for chemical syntheses if it could be obtained at a low enough cost. The article suggested that "propionic acid bacteria" might be used for this purpose.⁽⁸⁶⁾

Kluyver immediately saw an opportunity for a bacteriological investigation with both practical and theoretical interest. These organisms were already known to be important in the ripening of cheese, but they had not been studied systematically. Little was known about the biological characteristics of the propionic acid bacteria or how to culture them. In 1924, Kluyver proposed the investigation of the propionic acid bacteria as a subject for a prize competition in the laboratory.

Fascinated by the purple bacteria, van Niel had no intention of studying the propionic acid bacteria. Noticing a red spot on some cheese at breakfast one morning, however, van Niel was curious enough to take a sample to the laboratory and prepare a culture. The result was a flourishing population of propionic acid bacteria. He made a few basic experiments on their growth, which delighted Kluyver. He suggested that van Niel study the propionic acid bacteria for his dissertation.

It was a suggestion van Niel could not refuse. From 1926 to 1928, van Niel dutifully if unenthusiastically carried out a thorough study of the morphology and biochemistry of the propionic acid bacteria, their role in the ripening of cheese, and their potential use in industrial production. In some ways, it was a far cry from the "high culture" mode of science to which van Niel aspired. Van Niel's starting material for his study was Emmental cheese, some made in Holland and some from Switzerland. Among the problems addressed by van Niel's dissertation was the origin of the gas that causes holes to form in some types of cheese.

Van Niel's dissertation research followed a series of procedures that could be applied to any group of bacteria. It set a pattern of investigation he followed for the next three decades. The basic approach was to select a group of bacteria interesting for some reason and to undertake a systematic study of their morphology, physiology, biochemistry, and taxonomy. In this study, van Niel concluded with a section on technical applications. This section was omitted in his later works.

The first experimental step was to obtain cultures of the organisms from their natural environment. In this instance, the natural environment was cheese and other dairy products. The first step was to prepare enrichment cultures. At this stage, van Niel incubated particles of cheese in sample bottles containing a suitable culture medium. After a week, he tested the bottles for the presences of propionic acid. From the sample that produced the most propionic acid, he prepared new culture bottles. After another week of incubation, he took small aliquots of these cultures and streaked them onto culture plates containing solid media, in a manner that assured that each colony that appeared arose from a single cell. After repeating this procedure two or three times, it was possible to obtain a culture that contained only one species of bacteria.⁽⁸⁷⁾

Van Niel discovered as expected that the majority of strains isolated in this way belonged to the lactic acid group of bacteria. However, he was able to find on his plate-cultures a small number of colonies that differed morphologically and biochemically from the lactic acid bacteria. Van Niel succeeded in isolating these organisms, which proved to be propionic acid bacteria, from several kinds of cheese. He isolated thirty different strains in this manner.

Once he had obtained pure cultures of bacteria, van Niel examined them through a microscope and recorded detailed descriptions of their morphology under several different conditions. In sum, he observed that all thirty strains he prepared were Gram-positive, contained the enzyme catalase, were not motile, and did not make endospores or liquefy gelatine. In neutral media, the bacteria appeared as short rods. In acid media, however, the bacteria could appear in four different morphologies.⁽⁸⁸⁾

The next phase of van Niel's project was to investigate the biochemical properties of the propionic acid bacteria. The goal was to determine the reaction pathways that led from substrates to products, or the "chemism" of the process, as van Niel called it. Van Niel provided selected strains with a set of substrates, lactate, simple sugars, glycerol, and polyalcohols. He then determined quantitatively the ratio of fermentation products, propionic acid, acetic acid and CO₂. The study required a thorough knowledge of biochemical techniques. By comparing the biochemistry of many strains under different fermentation conditions, it was possible to make logical inferences of the identity of biochemical intermediates. For example, van Niel was able to conclude that the propionic acid bacteria produced metabolites containing three carbon atoms, or "C₃" compounds, from lactate without ever producing acetaldehyde as an intermediate.⁽⁸⁹⁾ This kind of conclusion, a small detail by itself, contributed to the increasingly substantial picture of the biochemical reactions carried out by bacteria.

Van Niel used both his morphological and biochemical characterizations to construct a new taxonomy of the propionic acid bacteria. This section of his dissertation was more biological in orientation than the others. Following the suggestion of earlier workers, van Niel agreed that the propionic bacteria were sufficiently like each other and different from other bacteria to be assigned to a single genus, Propionibacterium. Van Niel then went on to discuss the place of the genus in a natural bacterial system. Here van Niel came up against an issue that vexed him for the rest of his career: the urgent practical need for workable systems of bacterial classification and the compelling intellectual need to determine the evolutionary relationships of bacteria. Reflecting his interest in general biological theory, van Niel addressed the question of how bacterial phylogenies were to be determined, given the simple morphologies of these organisms compared to plants and animals.⁽⁹⁰⁾

In the last section of his dissertation, van Niel returned to more prosaic concerns. First, he reiterated the point that the propionic acid bacteria were crucial for the production of flavorful Emmental cheese. Then, he considered the possible applications of the propionic acid fermentation for the industrial manufacture of propionic acid. He pointed out that some of the strains he had isolated produced a very high proportion of propionic acid compared to other products and could be grown in an apparatus that allowed the easy separation of the propionic acid. He concluded, "the application of the propionic acid bacteria for the technical production of propionic acid can be very well realized."⁽⁹¹⁾

Van Niel's dissertation was typical of those produced from the Delft laboratory under Kluyver's direction.⁽⁹²⁾ From one point of view, van Niel's dissertation was a fundamental study of bacterial morphology and physiology. Its practical and technical aspects were striking, however, and could be emphasized to potential employers.

Kluyver anticipated that van Niel would work in industry and encouraged him to gain experience in practical research. In one project, van Niel studied the souring of cream, and isolated the chemical that causes the aroma of butter, for which he took out a patent. In 1923, Kluyver recommended van Niel to a Dutch dairy cooperative, which decided against hiring a bacteriologist at all, to Kluyver's annoyance.⁽⁹³⁾

Van Niel was probably not disappointed. Kluyver's efforts to turn van Niel's attention to practical work did not succeed. Van Niel turned down a position at the Yeast and Spirits Factory when told he would have to keep his results secret. He also expressed distaste for commercial activities.⁽⁹⁴⁾ Whether dazzled by Kluyver's theoretical program or for other reasons, van Niel developed an ideal of science more typical of theoretical physicists than civil engineers. Van Niel's explicit statements that he adhered to a conception of science as a kind of philosophical endeavor aimed at the cultivation of the mind occur in lectures he gave in the 1940's and 1950's. Decisions he made in Delft in the late 1920's are consistent with these values.

In many respects, van Niel's conception of science resembles what historian Jonathan Harwood has called the "comprehensive style."⁽⁹⁵⁾ In Harwood's interpretation, the comprehensive style characterizes scientists who considered research to be a philosophical and cultural pursuit, rather than a practical or technical endeavor. "Comprehensives" valued breadth rather than narrowness in their knowledge of science, were interested in philosophy and the fine arts, saw science as a means to cultivate the mind, and considered themselves to be above politics. This conception of science was widespread among European academics in the early twentieth century. Van Niel, too, adopted many of these attitudes. It is not entirely clear how he came to these views. It is possible that his circle of friends, which included writers and artists, shaped his perspectives.

Van Niel's ideal of science limited his career possibilities. In the depressed economy of the 1920's in the Netherlands, employment prospects were difficult even for those willing to work in industry. Institutionally, he was under severe constraints. By 1925, he had reached the highest position that he could attain at Delft, as "Conservator." In this capacity, he enjoyed some independence, but essentially functioned as a sort of assistant to Kluyver. Otherwise, there were few places in the world other than Delft where van Niel could practice microbiology as a fundamental science.

Van Niel's experience at Delft was crucial for his formation as a scientist. Van Niel was able to escape the constraints of his social origins because technical careers and a technical school like the THD existed in the 1920's. At the THD, he received thorough training in experimental quantitative sciences like basic physics and applied chemistry. At the same time, one of the few flourishing programs in general microbiology in the world was well-established there. He could develop a view of microbiology as a fundamental science because of the complex character of the work culture created by Kluyver. By 1928, van Niel was an accomplished microbiologist with a demonstrated talent for research. He was poised intellectually to embark on his own program of research. He lacked, however, an institutional position that would allow his potential to develop. His ideals and ambitions conflicted with his local opportunities.

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1. Charles E. Rosenberg makes this point in "Martin Arrowsmith: The Scientist as Hero," in No Other Gods: On Science and American Social Thought (Baltimore: Johns Hopkins University Press, 1997), 123-131.

2. Sinclair Lewis, Arrowsmith (New York: Harcourt Brace and World, 1952; originally published 1924), p. 386.

3. C.B. van Niel, "The Education of a Microbiologist: Some Reflections," Annual Review of Microbiology, 21 (1967), 1-30.

4. Ibid., p. 2.

5. For discussion of verzuiling, the subtle but rigid social structure in the Netherlands, see Frank E. Higgett, The Modern Netherlands (1971), pp. 68-78.

6. Van Niel, "Education," (1967), p. 2.

7. Ibid.

8. Ibid., pp. 2-5.

9. See, e.g., Robert E. Kohler, From Medical Chemistry to Biochemistry: The Making of a Biomedical Discipline (New York: Cambridge University Press, 1982); Gerald Geison and Frederick L. Holmes, eds., Research Schools: Historical Appraisals, Osiris, 8 (1993); Jonathan Harwood, Styles of Scientific Thought: The German Genetics Community, 1900-1933 (Chicago: University of Chicago Press, 1993); and Frederick L. Holmes, Between Biology and Medicine: The Formation of Intermediary Metabolism (Berkeley: Office for the History of Science and Technology, University of California; 1992) for a sampling of valuable analyses of these categories.

10. Lynn K. Nyhart, Biology Takes Form: Animal Morphology and the German Universities, 1800-1900 (Chicago: University of Chicago Press, 1995), p. 4.

11. Ibid., p. 4.

12. For institutions emphasizing general microbiology, Kohler identifies the Pasteur Institute, the Rockefeller Institute in New York, agricultural schools at the Universities of Iowa, Wisconsin and Helsinki, the biology departments at Stanford and the California Institute of Technology, the laboratory at Delft, the biochemistry department at Cambridge, and the bacteriology departments of Middlesex Hospital in London and the London School of Hygiene. See Robert E. Kohler, "Innovation in Normal Science: Bacterial Physiology," Isis, 76 (1985), 162-181 on p. 163.

13. See Paul F. Clark, Pioneer Microbiologists of America (Madison: University of Wisconsin Press, 1961); Patrick Collard, The Development of Microbiology (Cambridge: Cambridge University Press, 1976); Hubert A. Lechevalier and Morris Solotorovsky, Three Centuries of Microbiology (New York: McGraw Hill, 1965) for overviews from the 1870's to the 1940's.

14. Keith Vernon, "Pus, Sewage, Beer, and Milk: Microbiology in Britain," History of Science, 28 (1990), 289-325.

15. Clifford Dobell, Antony van Leeuwenhoek and his "Little Animals" (London: Staples Press, 1932).

16. Lechevalier and Solotorovsky, Three Centuries of Microbiology, pp. 3-4.

17. See William Coleman, Biology in the Nineteenth Century: Problems of Form, Function and Transformation (Cambridge: Cambridge University Press, 1977), pp. 22-23 for a summary.

18. Christian G. Ehrenberg, Die Infusionsthierchen als vollkommene Organismen: Ein Blick in das tiefere organische Leben der Natur (1838); cited in William Bulloch, The History of Bacteriology, (London: Oxford University Press, 1938), pp. 172-174.

19. Frederick B. Churchill, "The Guts of the Matter: Infusoria from Ehrenberg to Bütschli," Journal of the History of Biology, 22 (1989), 189-213.

20. See Pauline M.H. Mazumdar, Species and Specificity: An Interpretation of the History of Immunology (Cambridge: Cambridge University Press, 1995) for an insightful analysis of the Cohn's work in relation to debates about the stability of species of microorganisms.

21. Ferdinand Cohn, Über die Bacterien, die Kleinsten Lebenden Wesen (Berlin:Sammlung Gemeinverständlicher Wissenschaftlicher Vorträge, 1872). See Charles S. Dolley, "Bacteria. The Smallest of Living Organisms," Bulletin of the History of Medicine, 7 (1939), 48-92 for an English translation. Cohn's new classification of bacteria is discussed in Bulloch, History of Bacteriology (1938), pp. 176-78 and 193-210.

22. See Robert Bud, The Uses of Life: A History of Biotechnology (Cambridge: Cambridge University Press, 1993), Chapters I and II for discussion of science and the brewing industries in the late nineteenth century.

23. See Geison, Private Science of Pasteur (1995) for valuable interpretations of the many different aspects of Pasteur's career.

24. See Mazumdar, Species and Specificity (1995), Chapter III for discussion of the institutional and intellectual dominance of Koch and his students.

25. Barnett Cohen, Chronicles of the Society of American Bacteriologists (Baltimore: Williams & Wilkins Company, 1950).

26. Patricia Peck Gossel, "A Need for Standard Methods: The Case of American Bacteriology," in Adele E. Clarke and Joan Fujimori, eds. The Right Tools for the Job (Princeton: Princeton University Press, 1991), 287-311.

27. Sedgwick, "Significance of Bacteriology," (1901).

28. W.T. Sedgwick, "The Origin, Scope and Significance of Bacteriology," Science, XIII (1901), 121-28. See also W.T. Sedgwick, "The Genesis of a New Science--Bacteriology," Journal of Bacteriology, 1 (1916), 5-15; and J. Howard Brown, "The Biological Approach to Bacteriology," Journal of Bacteriology, 23 (1932), 1-10.

29. See Kohler, From Medical Chemistry to Biochemistry (1982) for discussion of the importance to successful discipline building of securing service roles.

30. This group was led by the philosopher Cornelis Opzoomer, and included the zoologist Pieter Harting and the chemist Gerrit Jan Mulder. I have relied here on the work of Bert Theunissen. For extensive discussion, see Bert Theunissen, "Knowledge is Power: Hugo de Vries on Science, Heredity, and Social Progress," British Journal for the History of Science, 27 (1994), 291-311. See also Bert Theunissen and Frans van Lunteren, eds, "Zuievere Wetenschap and Praktisch Nut: Visies op de Maatschappelijke Betekenis van Wetenschappelijk Onderzoek Rond 1900," special issue of Gewina (1994).

31. Cornelis Disco, Made in Delft: Professional Engineering in the Netherlands 1880-1940, dissertation, University of Amsterdam, 1990.

32. Disco, Made in Delft (1990), 44-45, 48-49, 57. See also Harry Lintsen, Ingeniurs in Nederland in de Negentiende Eeuw; Een streven naar erkenning en macht (1980).

33. Disco, Made in Delft (1990), p. 61.

34. See ibid., pp. 88-97, for analysis of the social origins of matriculants at Delft from 1880 to 1920.

35. Theunissen, "Hugo de Vries on Science, Heredity, and Social Progress," (1994), 291-311; Theunissen and Lunteren, eds, "Zuievere Wetenschap and Praktisch Nut," (1994).

36. See Ronald Kline, "Construing 'Technology' as 'Applied Science': Public Rhetoric of Scientists and Engineers in the United States, 1880-1945," Isis, 86 (1995), 194-221, for detailed analysis of the meaning of these categories and their rhetorical use by scientists and engineers in the professionalization process in the US.

37. George H. Daniels, "The Pure-Science Ideal and Democratic Culture," Science, 156 (1967) 1699-1705 on p. 1701.

38. H. Holter and K. Max Møller, The Carlsberg Laboratory 1876-1976 (Copenhagen: Rhodos International Science and Art Publishers, 1976).

39. Bert Theunissen, "Martinus Willem Beijerinck and the 'Delft Tradition in Microbiology," in Piet Bos and Bert Theunissen, eds., Beijerinck and the Delft School of Microbiology (Delft: Delft University of Technology Press, 1995); and G. van Iterson, L.E. den Dooren de Jong, and A.J. Kluyver, "Martinus Willem Beijerinck, His Life and Work," in Verzamelde Geschriften van M.W. Beijerinck, volume 6, ('S-Gravenhage: Martinus Nijhoff, 1940).

40. Van Iterson et al., "Beijerinck. Life and Work," (1940), pp. 18 and 101.

41. Ibid., pp. 102-09.

42. Ibid., pp. 20-22.

43. M.W. Beijerinck, "De biologische wetenschap en de bacteriologie. Redevoering gehouden bij de opening der Lessen in de Bacteriologie aan de Polytechnische School, Donderdag 26 September, 1895;" in Verzamelde Geschriften van M.W. Beijerinck, volume 3 ('S-Gravenhage: Martinus Nijhoff, 1940).

44. Theunissen, "Beijerinck," (1995); and van Iterson et al., "Beijerinck. Life and Work," (1940).

45. This point is emphasized by Theunissen, "Beijerinck," (1995).

46. Van Iterson et al., "Beijerinck. Life and Work," (1940), pp. 121-122.

47. Ibid., pp. 125-128, 130-134.

48. Ibid., pp. 118-121. The Russian researcher D. Iwanoski reached similar conclusions five years before Beijerinck. Iwanoski assumed the factor was a kind of bacterium.

49. In a truly remarkable assessment of parentage, Beijerinck was called "the father, the mother and the founder of modern virology," on the occasion of the centennial of the laboratory in Delft in December 1995.

50. Quoted by C.B. van Niel, "The 'Delft School' and the Rise of General Microbiology," Bacteriological Reviews, 13 (1949), 161-174 on p. 163.

51. Van Iterson et al., "Beijerinck. Life and Work," (1940), pp. 138-144.

52. Theunissen, "Beijerinck," (1995).

53. Van Iterson et al., "Beijerinck. Life and Work," (1940), p. 30.

54. Van Niel, "Education," (1967), p. 3.

55. Ibid., pp. 3-5.

56. Ibid.

57. Ibid., pp. 1-7.

58. Van Iterson et al., "Beijerinck. Life and Work," (1940), pp. 33-34.

59. For additional biographical information, see A.R. Kamp, J.W.M. La Rivière, and W. Verhoeven, eds., Albert Jan Kluyver: His Life and Work (Amsterdam: North Holland, 1959).

60. Beijerinck to den Dooren de Jong, July 28, 1926; MWB.

61. Theunissen, "Beijerinck," (1995), pp. 187-89.

62. Kamp et al., Kluyver (1959), p. 165.

63. Ibid., pp. 167-68.

64. Ibid., pp. 177-78.

65. Ibid., pp. 165-185.

66. See Olga Amsterdamska, "Beneficent Microbes: The Delft School of Microbiology and its Industrial Connections," in Piet Bos and Bert Theunissen, eds., Beijerinck and the Delft School of Microbiology (Delft: Delft University of Technology Press, 1995), for a detailed and insightful analysis of how Kluyver successfully pursued both his theoretical and practical agendas. The following section relies heavily on her work.

67. Kamp et al., Kluyver (1959), pp. 81-82.

68. Ibid., pp. 82-83.

69. A.J. Kluyver, "Eenheid en verscheidenheid in de stofwisseling der microben," Chemische Weekblad, 21 (1924), p. 266; translated in Kamp et al., Kluyver (1959), pp. 186-210.

70. Kamp et al., Kluyver (1959) p. 87; Amsterdamska, "Benificent Microbes," (1995).

71. J.L. Heilbron, The Dilemmas of an Upright Man (Berkeley: University of California Press, 1986), pp. 47-49, 138-39.

72. See V.B. Smocovitis, "Unifying Biology: The Evolutionary Synthesis and Evolutionary Biology" Journal of the History of Biology, 25 (1992), 1-65 for an extended discussion of the relationships among the unity of science movement, logical positivism, and biological thought, especially the evolutionary synthesis.

73. See e.g. William Emerson Ritter, The Unity of the Organism (Boston: R.G. Badger, 1919) and Chapter III below for discussion of the "unity of life" among life scientists in the early twentieth century.

74. Harmke Kamminga and Mark W. Weatherall. "The Making of a Biochemist: I. Frederick Gowland Hopkins's Construction of Dynamic Biochemistry," Medical History, 40 (1996), 269-292.

75. Garland E. Allen, Life Sciences in the Twentieth Century (Cambridge: Cambridge University Press, 1975) p. 180. See Petra Werner "Learning from an Adversary? Warburg against Wieland," Historical Studies in the Philosophical and Biological Sciences, 28 (1997), 173-196, for a detailed study of the controversy.

76. A. J. Kluyver, The Chemical Activities of Micro-organisms (London: University of London Press, 1931), p. 5.

77. Ibid., p. 11.

78. Ibid., p. 94.

79. Allen, Life Sciences (1975), pp. xxi-xxiii.

80. Kluyver, Chemical Activities of Micro-organisms (1931), p. 95.

81. Amsterdamska, "Beneficent Microbes," (1995), pp. 204-10.

82. Kamp et al, Kluyver (1959), p. 24; Amsterdamska, "Beneficent Microbes," (1995).

83. Van Niel, "Education," (1967), pp. 7-8.

84. Ibid., pp. 8-9.

85. Ibid., pp. 9-11.

86. Whittier and J.M. Sherman, Journal of Industrial and Engineering Chemistry, 15 (1923), p. 729.

87. C.B. van Niel, The Propionic Acid Bacteria (Haarlem: N.V. Uitgeverszaak J.W. Boissevain & Co., 1928), pp. 51-66.

88. Ibid., pp. 67-78.

89. Ibid., pp. 79-158.

90. Ibid., pp. 159-180.

91. Ibid., pp. 181-87.

92. See Kamp et al., Kluyver (1959), pp. 537-539, for a list of dissertations prepared under Kluyver.

93. Amsterdamska, "Benificent Microbes," (1995) pp. 200-201.

94. Van Niel, "Education," (1967), pp. 13-14.

95. Harwood, Styles of Scientific Thought (1993), pp. 189-190, 276-83.