SCIENCE AND TECHNOLOGY

The view that science somehow leads to technology through the model known oddly as the "linear model" fared poorly in the late twentieth century. The linear model has it that in the past, pure science led to applied science, applied science to technology, and from there the path led to engineering and production. Among late-twentieth- and early-twenty-first-century scholars, however, there is consensus: first, that technology drove science at least as much as the reverse; second, that scientific under-standing—whatever that precisely means—is neither a necessary nor a sufficient condition for technological progress; and third, that both are deeply influenced by a host of cultural, social, and economic factors too numerous and in dispute to list here. There is a danger that in their haste to criticize the highly simplified and schematic model, critics will end up without an appreciation of the importance of scientific knowledge in the process of technological and economic development between 1780 and 1914. Every technique has an "epistemic base"—that is, knowledge about natural regularities and phenomena—on which it rests. At times this basis is very narrow or barely even exists; in those cases, the technique in question works, but nobody is quite sure how and why. In other instances, some minimum has to be known before the technique can be realized.

the interplay between technology and science

Perhaps the safest generalization one can make is that there was no single model or straightforward relationship between scientific knowledge and technological practice. Each industry and each practice differed in its need to rely on the formalized knowledge that was still known as "natural philosophy" in 1780. In the ensuing "long nineteenth century" (1789–1914), a large number of important inventions were made that owed little to science. This would include most breakthroughs in the textile industry; some of the canonical inventions that revolutionized the cotton industry were tricky mechanical problems that took mechanical ingenuity to solve, but "science" as such had little to do with their solution. Similarly, the invention of barbed wire by Joseph Farwell Glidden (1813–1906) in 1874, while of substantial significance to the American agricultural economy, owed nothing to science. A common story is that science discovers some phenomenon that can be exploited. The technique that emerges subsequently serves as a focusing device that makes scientists take a closer look, and as they begin to understand the underlying natural processes better and better, they can improve the technique and adapt it to new uses.

The paradigmatic example is of course steam power. By 1780 steam power was on its way to assume a central role in the industrialization and transportation revolution. The "science" behind it was nontrivial: to build an atmospheric engine, one had to know at least that the earth's surface was at the bottom of an atmosphere, whose pressure could be

exploited. James Watt's (1736–1819) improvements to Thomas Newcomen's (1663–1729) steam engine depended in part on the further realization, due to his fellow Scotsman William Cullen (1710–1790), that in a vacuum water boils at much lower, even tepid, temperatures, releasing steam that would ruin the vacuum in a cylinder. Yet "understanding" steam power in a way that would conform to our notions of science was still many decades off: in the 1820s and 1830s, the best theorists of steam power still regarded it as a vapor engine rather than recognizing it for the heat engine it was. Inspired and focused by the steam engines they observed, the great theorists of thermodynamics such as Sadi Carnot (1796–1832) and James Prescott Joule (1818–1889) finally formulated the science of thermodynamics. Technology did not "depend" on science, but better science could improve it to the point where the productivity growth due to continuous improvements drove economic growth.

Another example is the electromagnetic telegraph, one of the truly transforming inventions of the nineteenth century. Here, too, some science was necessary to make it possible. In this case, it was the discovery that electricity and magnetism were related after all (something that had been in serious doubt). In 1819 a Danish physicist, Hans Christian Oersted (1777–1851), brought a compass needle near a wire through which a current was passing. It forced the needle to point at a right angle to the current. A number of scientists put their mind to the problem, and by the mid-1830s Joseph Henry (1797–1878) and others realized that an electro-magnetic telegraph was possible, and by 1837 the device was shown to work.

Yet the epistemic base was still quite narrow, and it took the genius and energy of William Thomson (1824–1907, later Lord Kelvin) to work out the principles governing the relation between the signal and the resistance, inductive capacity, and length, and to compute the resistivity of copper and the inductive capacity of gutta-percha, the insulating material. He used his knowledge to invent a special galvanometer, a siphon recorder (which automatically registered signals), and a technique of sending short reverse pulses immediately following the main pulse to sharpen the signal. These inventions were based on best-practice mathematical physics, and although the epistemic base was far from complete (Kelvin resisted the electromagnetics of James Clerk Maxwell [1831–1879] and held on to the notion of ether, believed to be the weightless medium for the transmission of electromagnetic waves), they improved the telegraph in every direction.

A third example of the subtle interplay between science and technology in the nineteenth century is found in soil chemistry. Since antiquity, farmers had realized that they could improve agricultural output by adding certain substances to the soil. Among those substances, animal manure and marl were widely used. Nobody, of course, quite under-stood how and why these procedures worked, and as a result progress in agricultural productivity was limited when judged by the standards of later development. By 1800 agricultural writers were busy cataloging what kind of substances worked on which soils and for what crops, but the epistemic base this practice remained rather narrow and consisted mostly of empirical patterns that these writers thought they were observing. However, the closing decades of the eighteenth century saw the rise of modern chemistry, and by the 1820s and 1830s, German chemists led by Friedrich Wöhler (1800–1882) and Justus von Liebig (1803–1873) discovered what today is called organic chemistry and realized that it helped them understand why certain substances such as phosphates and nitrates improved agricultural productivity. By midcentury, the important role of various chemical substances was better understood, and European farmers began to apply potash and nitrates to their soils. The greatest triumph of science was beyond question the distillation of ammonia from the atmosphere: nitrates were recognized as an essential ingredient in both fertilizers and explosives, yet although most of the atmosphere consists of nitrogen, it was not known how to extract it. Fritz Haber (1868–1934) and Carl Bosch (1874–1940) solved this problem around 1910. Both were highly trained professional chemists, yet their process still relied on a great deal of trial-and-error research.

Perhaps nowhere are the complexities of the relation between science and technology better illustrated than in medical technology. The growth of medical science was unusually slow. It is not an exaggeration to point out that by 1800, medical science had developed little beyond the great medical writers of antiquity. Theories of disease were confused and mutually contradictory, and the ability of science to prevent, let alone cure, often-fatal infectious diseases was negligible. This started to change in the early nineteenth century due to two major developments. The first is the recognition that relatively poorly understood natural phenomena can be analyzed by means of statistical data. On that account, for instance, it became clear through the research of the French physician Pierre-Charles-Alexandre Louis (1787–1872) around 1840 that bleeding ill patients did little to improve their health, and (through the work of British physicians such as John Snow [1813–1858] and William Budd [1811–1880] in the 1850s) that water that appeared and tasted clean could still transmit deadly diseases. As a result, a great deal of effort was directed toward filtering the water supply and separating drinking

water from waste decades before the actual epistemic base of infectious diseases was established by Louis Pasteur (1822–1895) and Robert Koch (1843–1910) in the 1860s and 1870s. Following Pasteur and Koch, however, it not only became clear how and why Louis and Snow had been correct, but also how to apply this knowledge to further advance private and public health through preventive medicine. Pasteur's science helped change and improve the technology of surgery as much as it improved that of food canning—even if both had existed before his work.

drivers and incentives in knowledge production

The model that scientific knowledge somehow "leads" to technology is an oversimplification for another reason as well. Science is more than just the formal and consensual knowledge familiar to the twenty-first century. The heritage of the eighteenth century to the modern age and the taproot of technological progress and economic growth was a radically different view of why and how science should be practiced. Curiosity and "wisdom" had to make room for another set of motives—namely, the growing conviction that understanding nature was the key to controlling it, and that controlling nature was in turn the key to technological and economic progress.

This attitude, often traced back to Francis Bacon (1561–1626), became more and more influential in the eighteenth century. It involved the separation of scientific practice from religion, the belief that nature was orderly, and that natural laws, once properly formulated, were universal with no exceptions (i.e., magic). It involved major cultural changes, above all the practice of "open science" (that is, placing scientific findings in the public realm), that had emerged during the Renaissance but only became unequivocally established during the second half of the seventeenth century. Open science did two things. First, it made scientific knowledge available to those who might be able to use it. Second, it increased the credibility of scientific knowledge by exposing it to the scrutiny and criticism of other experts. It was widely believed—often somewhat over-optimistically—that once scientific claims had been exposed to the rest of the world, those that survived must be correct. Scientists were rewarded by fame, prestige, and at times comfortable and secure positions, but they sought credit, not profit.

By 1780 the realm of useful knowledge had bifurcated into knowledge that was "propositional" (including science, mathematics, geography, and a catalog of successful techniques) in that it stated discoveries about nature and placed them in the public realm, and knowledge that was "prescriptive," that is, provided the actual instructions on how to produce. The latter kind of knowledge was increasingly driven by profit motives, and for it to keep expanding, it needed to secure a way of compensating inventors for their efforts and investments. This could be (and was) done in a variety of ways. One was to secure intellectual property rights in the form of patents, which would place the knowledge in the public realm but prohibit its exploitation without the permission of the patentee. The second was to keep the invention secret, a strategy that could work at best only if the innovation could not be reverse-engineered. The third was to reward the inventor through some formal government body that assessed the value to society of this knowledge and paid the inventor from the public treasury. Finally, a few inventors simply relied on the advantage of being the first mover; they knew they would be imitated but hoped to make enough money simply by getting there first.

access and progress

In any event, the central factor in the growth of technology in the period from 1780 to 1914 was the continuous improvement in the access to useful knowledge. Knowledge meant both power and prosperity, but only if it could be accessed by those best able to exploit it. At times, of course, scientists rolled up their sleeves and applied their knowledge to new techniques themselves. The modern-age specialization between ivory-tower theorists and practically minded engineers and inventors (more of a stereotype than a reality even in the twenty-first century) was comparatively rare in the period of the First Industrial Revolution. Many theorists and experimentalists became interested in and solved applied production problems. The great chemist Humphry Davy (1778–1829), to cite one example, invented the mining safety lamp, wrote a textbook on agricultural chemistry, and discovered that a tropical plant named catechu was a useful additive to tanning. His colleague Benjamin Thompson (Count Rumford, 1753–1814) was most famous for the proof that heat is not a liquid (known as "caloric") that flows in and out of substances. Yet Rumford was deeply interested in technology, helped establish the first steam engines in Bavaria, and invented (among other things) the drip percolator coffeemaker, a smokeless-chimney Rumford stove, and an improved oil lamp. In the later nineteenth century, the physicist Joseph Henry (1797–1878) probably can make a good claim to being the inventor of the electromagnetic telegraph, and Lord Kelvin owned dozens of patents.

Communication between scientists and manufacturers became a matter of routine in the late eighteenth and nineteenth centuries. Such access is essential if the growth in useful knowledge is to have economic consequences. Early on, such contact often took place in meeting places and scientific societies that became typical of Enlightenment Europe. Of those, most famous were the Birmingham Lunar Society, in which manufacturers such as Josiah Wedgwood (1730–1795) and Matthew Boulton (1728–1809) picked the brains of scientists such as Joseph Priestley (1733–1804) and Erasmus Darwin (1731–1802), and the London Chapter Coffee House, which boasted a similarly distinguished clientele. The Royal Institution, founded in 1800, provided public lectures for the general public.

During the nineteenth century, the number of forums in which manufacturers and engineers could meet and communicate with scientists increased rapidly. Scientists were often retained as consultants and inventors. The German chemical

and electrical firms, which carried out a substantial amount of the research and development that created the Second Industrial Revolution, often retained university professors who practiced a "revolving door" kind of career between their academic and industrial jobs. Thomas Edison (1847–1931), whose knowledge of science was intuitive rather than formal, employed a number of highly trained scientists with whom he consulted, though at times he wisely chose to ignore their advice. Yet what has to be realized is that personal contact was only necessary insofar that knowledge could not be codified—that is, described and depicted in words or pictures.

The proliferation of scientific and technological literature in the nineteenth century was simply enormous. This proliferation took the form of encyclopedias, textbooks, manuals, as well as scientific periodicals of many varieties. Libraries sprang up everywhere and the declining real price of books and printed matter made for an ever-growing accessibility of scientific and mathematical knowledge to those who could make use of it. Equally important, engineering education became increasingly science-based. In the French grandes écoles and in the German universities, mining academies, and technical colleges, formal science became part of the education of even midlevel technicians. Inventing remained, as it is in the twenty-first century, open to "tinkerers" such as Sir Henry Bessemer (1813–1898), Sidney Gilchrist Thomas (1850–1885), and Edison. Yet their inventions, no matter how brilliant, only worked because they were subsequently refined and improved by people well trained in the relevant science.

Of course, some classic inventions originally were simply mechanical. The zipper (patented in 1893 by Whitcomb Judson) and paper clips (introduced by the Gem company in Britain in the 1890s) were much like barbed wire, simple and useful ideas that needed no science. But even in many cases of simple inventions, knowledge of the finer details of metallurgy, electricity, or mass production engineering was needed for further development.

feedback from technology to science

The interplay of science and technology in the nineteenth century was bidirectional and can be viewed as positive feedback in the sense that technology helped science just as science helped technology. Such positive feedback mechanisms often lead to unstable systems that never converge to a given position. While such a view may be unsettling to scholars who like to think of the world as inherently stable and predictable, it is perhaps not an inappropriate way of viewing the historical process of technological change from 1780 to 1914, a period that displays continuous unpredictable change as its most enduring feature.

The ways in which technology affected science can be viewed in three broad categories. First, as already been shown, technological practices directed and focused the interests of researchers to discover how and why they worked. The search for the deep nature of electricity spurred the work of such scientists as Svante August Arrhenius (1859–1927), George Johnstone Stoney (1826–1911), and Sir Joseph John Thomson (1856–1940), leading to the discovery of the electron. It is almost comical to contemplate Thomson's alleged toast at an event celebrating his Nobel Prize in physics: "Here's to the electron, may no one ever find a use for it." By that time, of course, electrical lighting and appliances were ubiquitous. The practice of food canning, invented by Nicolas Appert (1749–1841) in 1795, stimulated Pasteur into his famous studies of putrefaction.

Or consider geology: the need to develop a better method to prospect for coal inspired William Smith (1769–1839) toward a growing understanding of geology and the ability to identify and describe strata on the basis of the fossils found in them. The idea (already widely diffused on the Continent but unknown to Smith) that there were strong natural regularities in the way geological strata were layered led to the first geological maps, including Smith's celebrated Geologic Map of England and Wales with Part of Scotland (1815), a "map that changed the world." It increased the epistemic base on which mining and prospecting for coal rested. One can track with precision where and through which institutions this interaction between propositional and prescriptive knowledge took place and the institutional environment that made them possible. Although the marriage between geology and mining took a long time to yield results, the widening epistemic base in nineteenth-century mining technology surely was the reason that the many alarms that Britain was exhausting its coal supplies turned out to be false.

Technology also stimulated science by allowing it to carry out new research. The extent to which science was constrained by instruments and tools is rarely fully appreciated. Astronomy, it has often been observed, entered a new age the day that Galileo Galilei (1564–1642) aimed his brand-new telescope toward the sky. Microscopy had a similar effect on the world of microorganisms. The invention of the modern compound microscope by Joseph Jackson Lister (1786–1869, father of the surgeon) in 1830 serves as another good example. Lister was an amateur optician, whose revolutionary method of grinding lenses greatly improved image resolution by eliminating spherical aberrations. His invention changed microscopy from an amusing diversion to a serious scientific endeavor and eventually allowed Pasteur, Koch, and their disciples to refute spontaneous generation and to establish the germ theory. The chemical revolution initiated by Antoine Laurent Lavoisier (1743–1794) and his French collaborators might not have achieved such a triumph had he not been equipped with unusually precise instruments. The famous mathematician Pierre-Simon de Laplace (1749–1827) was also a skilled designer of equipment and helped to build the calorimeter that resulted in the celebrated Memoir on Heat by Laplace and Lavoisier (1783), in which respiration was identified as analogous to burning. Much of the late-eighteenth-century chemical revolution was made possible by new instruments such as Alessandro Volta's (1745–1827) eudiometer, a glass container with two electrodes intended to measure the content of air, used by Henry Cavendish (1731–1810) to show the nature of water as a compound.

Perhaps the classic case of an invention that enabled scientific progress was the Voltaic Pile, the first battery that produced continuous current, invented by Volta in 1800. Through the new tool of electrolysis, pioneered by William Nicholson (1753–1815) and Davy, chemists were able to isolate element after element and fill in much of the detail in the maps whose rough contours had been sketched by Lavoisier and John Dalton (1766–1844). Volta's pile, as Davy put it, acted as an "alarm bell to experimenters in every part of Europe." Electrochemistry became the tool with which much of the chemical revolution was placed on a firm and systematic footing. For instance, Davy established that chlorine, the miraculous bleaching substance that played such a major role in the new cotton industry, was an element and not a compound.

Finally, technology often made it possible to verify and test scientific hypotheses and to decide scientific controversies. Much science is the subject of endless debate, and nothing will settle a scientific debate as effectively as a demonstrable useful application. The success of Koch and his followers in identifying a host of bacterial pathogens and the subsequent advances in public and private health helped wipe out whatever doubt there remained about the validity of the germ theory. Heinrich Rudolph Hertz's (1857–1894) work on oscillating sparks in the 1880s and the subsequent development of wireless communications by Sir Oliver Joseph Lodge (1851–1940) confirmed Maxwell's purely theoretical work on electromagnetic fields.

Most decisively, the success of the Wright brothers at Kitty Hawk in 1903 resolved the dispute among physicists on whether heavier-than-air machines were feasible. In 1901 the astronomer and mathematician Simon Newcomb (1835–1909, the first American since Benjamin Franklin [1706–1790] to be elected to the Institute of France) had still opined that flight carrying anything

more than "an insect" would be impossible. Here, too, theory and practice worked cheek-by-jowl. The Wright brothers worked closely with Octave Chanute (1832–1910), the leading aeronautical engineer of the age. Yet it was only following their successful flight that Ludwig Prandtl (1875–1953) published his magisterial work on how to compute airplane lift and drag using rigorous methods.

could economic growth have taken place without science?

It is often argued that the First Industrial Revolution (1760–1830) owed little to formal science. Most of the pathbreaking inventions such as Sir Richard Arkwright's (1732–1792) throstle (1769) or Henry Cort's (1740–1800) puddling and rolling technique (1785) were independent of the scientific advances of the age. While it is easy to show scientific progress during the Industrial Revolution, it is not easy to come up with many mechanical inventions that required advanced scientific knowledge as such. There are, of course, a few such instances, but before the middle of the nineteenth century they were not the rule.

In other words, scientific knowledge before 1850 was an input in innovation, but its importance was not decisive. Perhaps the best way of thinking about it is to realize that in addition to science affecting technology and vice versa, both were affected by a culture of growing material rationalism associated with the Industrial Enlightenment. It is interesting, however, to note that the major inventors of the time increasingly felt that they needed science and scientists to help them. Watt's milieu of scientists in Glasgow (and later Birmingham), Wedgwood's prodding of scientists (including Lavoisier himself) for advice on the technical problems that came up with his pottery, or the obsession of Leeds woolen manufacturer Benjamin Gott (1762–1840) with scientific experiment and chemistry demonstrate that such beliefs were widespread, at least in the circles that counted most.

As the nineteenth century advanced, such expectations were increasingly realized. One of the less well-known consequences of the chemical revolution is the work of the French chemist Michel-Eugène Chevreul (1786–1889), who discovered in the 1820s the nature of fatty acids and turned the manufacture of soap and candles from an art into a science. As director of dyeing at the Manufacture des Gobelins, he had a direct interest in the chemistry of dyes and colors. The original work on the chemistry of dyeing had been carried out by his predecessor at the Gobelins, Claude-Louis Berthollet (1748–1822, famous for the discovery of the bleaching properties of chlorine), but his work had been cut short by his political activities and it fell to Chevreul to realize his program.

The progress of steel, one of the truly central inventions that heralded in the Second Industrial Revolution, too, depended on science more than the usual story of the invention of the Bessemer process suggests. The epistemic base of steelmaking at the time was larger than Sir Henry Bessemer's (1813–1898) knowledge. This was demonstrated when an experienced and trained metallurgist named Robert Forester Mushet (1811–1891) showed that Bessemer steel contained excess oxygen, a problem that could be remedied by adding a decarburizer consisting of a mixture of manganese, carbon, and iron. In the years following Bessemer and Mushet's work, the Siemens Martin steelmaking process was perfected, and Henry Clifton Sorby (1826–1908) discovered the changes in crystals in iron upon hardening and related the trace quantities of carbon and other constituents to the qualities and hardness of steel. Steelmaking may not have been "scientific" in the modern sense of the word, but without the growing science of metallurgy, its advance eventually would have been stunted.

Economic growth can take place in the absence of advances in knowledge, but when it does so, it usually is more vulnerable and harder to sustain over long periods and large areas. When it is based on advances in knowledge, it is much less likely to be reversed. The twentieth century made a serious attempt to return to barbarism and to undo the advances of the years from 1780 to 1914, but in the end progress was resumed and has led to the stupefying growth in riches of the post-1950 decades.

The "Great Synergy," as Vaclav Smil has referred to it, between science and technology (or perhaps between propositional and prescriptive knowledge) is the central event of modern European history. It led to sustained and irreversible gains in productivity and quality of life, to the doubling of life expectancy, and to the realization of lifestyles that in 1780 must have seemed unimaginable in their material comfort and opulence.

See alsoAgricultural Revolution; Industrial Revolution, Second.

bibliography

Headrick, Daniel R. When Information Came of Age: Technologies of Knowledge in the Age of Reason and Revolution, 1700–1850. Oxford, U.K., 2000.

Jacob, Margaret C. Scientific Culture and the Making of the Industrial West. New York, 1997.

Jacob, Margaret C., and Larry Stewart. Practical Matter: Newton's Science in the Service of Industry and Empire, 1687–1851. Cambridge, Mass., 2004.

Mokyr, Joel. The Lever of Riches: Technological Creativity and Economic Progress. New York, 1990.

——. The Gifts of Athena: Historical Origins of the Knowledge Economy. Princeton, N.J., 2002.

——. "The Intellectual Origins of Modern Economic Growth." Journal of Economic History 65, no. 2 (2005): 285–351.

Musson, A. E., and Eric Robinson. Science and Technology in the Industrial Revolution. Manchester, U.K., 1969.

Petrosky, Henry. Invention by Design: How Engineers Get from Thought to Thing. Cambridge, Mass., 1996.

Rosenberg, Nathan. Perspectives on Technology. Cambridge, U.K., 1976.

——. "How Exogenous Is Science?" In his Inside the Black Box: Technology and Economics. Cambridge, U.K., 1982.

Smil, Vaclav. Creating the Twentieth Century: Technical Innovations of 1867–1914 and Their Lasting Impact. New York, 2005.

Smith, Crosbie, and M. Norton Wise. Energy and Empire: A Biographical Study of Lord Kelvin. Cambridge, U.K., 1989.

Winchester, Simon. The Map That Changed the World: The Tale of William Smith and the Birth of a New Science. London, 2001.

Joel Mokyr