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Although Newton was unable to bring to chemistry the kind of clarification he brought to physics, the Opticks did provide a method for the study of chemical phenomena. One of the major advances in chemistry in the 18th century was the discovery of the role of air, and of gases generally, in chemical reactions. This role had been dimly glimpsed in the 17th century, but it was not fully seen until the classic experiments of Joseph Black on magnesia alba (basic magnesium carbonate) in the 1750s. By extensive and careful use of the chemical balance, Black showed that an air with specific properties could combine with solid substances like quicklime and could be recovered from them. This discovery served to focus attention on the properties of “air,” which was soon found to be a generic, not a specific, name. Chemists discovered a host of specific gases and investigated their various properties: some were flammable, others put out flames; some killed animals, others made them lively. Clearly, gases had a great deal to do with chemistry.

The Newton of chemistry was Antoine-Laurent Lavoisier. In a series of careful balance experiments Lavoisier untangled combustion reactions to show that, in contradiction to established theory, which held that a body gave off the principle of inflammation (called phlogiston) when it burned, combustion actually involves the combination of bodies with a gas that Lavoisier named oxygen. The chemical revolution was as much a revolution in method as in conception. Gravimetric methods made possible precise analysis, and this, Lavoisier insisted, was the central concern of the new chemistry. Only when bodies were analyzed as to their constituent substances was it possible to classify them and their attributes logically and consistently. The imponderable fluids

The Newtonian method of inferring laws from close observation of phenomena and then deducing forces from these laws was applied with great success to phenomena in which no ponderable matter figured. Light, heat, electricity, and magnetism were all entities that were not capable of being weighed—i.e., imponderable. In the Opticks, Newton had assumed that particles of different sizes could account for the different refrangibility of the various colours of light. Clearly, forces of some sort must be associated with these particles if such phenomena as diffraction and refraction are to be accounted for. During the 18th century, heat, electricity, and magnetism were similarly conceived as consisting of particles with which were associated forces of attraction or repulsion. In the 1780s, Charles-Augustin de Coulomb was able to measure electrical and magnetic forces, using a delicate torsion balance of his own invention, and to show that these forces follow the general form of Newtonian universal attraction. Only light and heat failed to disclose such general force laws, thereby resisting reduction to Newtonian mechanics. Science and the Industrial Revolution

It has long been a commonsensical notion that the rise of modern science and the Industrial Revolution were closely connected. It is difficult to show any direct effect of scientific discoveries upon the rise of the textile or even the metallurgical industry in Great Britain, the home of the Industrial Revolution, but there certainly was a similarity in attitude to be found in science and nascent industry. Close observation and careful generalization leading to practical utilization were characteristic of both industrialists and experimentalists alike in the 18th century. One point of direct contact is known: namely, James Watt’s interest in the efficiency of the Newcomen steam engine, an interest that grew from his work as a scientific-instrument maker and that led to his development of the separate condenser that made the steam engine an effective industrial power source. But, in general, the Industrial Revolution proceeded without much direct scientific help. Yet the potential influence of science was to prove of fundamental importance.

What science offered in the 18th century was the hope that careful observation and experimentation might improve industrial production significantly. In some areas, it did. The potter Josiah Wedgwood built his successful business on the basis of careful study of clays and glazes and by the invention of instruments like the pyrometer with which to gauge and control the processes he employed. It was not, however, until the second half of the 19th century that science was able to provide truly significant help to industry. It was then that the science of metallurgy permitted the tailoring of alloy steels to industrial specifications, that the science of chemistry permitted the creation of new substances, like the aniline dyes, of fundamental industrial importance, and that electricity and magnetism were harnessed in the electric dynamo and motor. Until that period science probably profited more from industry than the other way around. It was the steam engine that posed the problems that led, by way of a search for a theory of steam power, to the creation of thermodynamics. Most importantly, as industry required ever more complicated and intricate machinery, the machine tool industry developed to provide it and, in the process, made possible the construction of ever more delicate and refined instruments for science. As science turned from the everyday world to the worlds of atoms and molecules, electric currents and magnetic fields, microbes and viruses, and nebulae and galaxies, instruments increasingly provided the sole contact with phenomena. A large refracting telescope driven by intricate clockwork to observe nebulae was as much a product of 19th-century heavy industry as were the steam locomotive and the steamship.

The Industrial Revolution had one further important effect on the development of modern science. The prospect of applying science to the problems of industry served to stimulate public support for science. The first great scientific school of the modern world, the École Polytechnique in Paris, was founded in 1794 to put the results of science in the service of France. The founding of scores more technical schools in the 19th and 20th centuries encouraged the widespread diffusion of scientific knowledge and provided further opportunity for scientific advance. Governments, in varying degrees and at different rates, began supporting science even more directly, by making financial grants to scientists, by founding research institutes, and by bestowing honours and official posts on great scientists. By the end of the 19th century the natural philosopher following his private interests had given way to the professional scientist with a public role. The Romantic revolt

Perhaps inevitably, the triumph of Newtonian mechanics elicited a reaction, one that had important implications for the further development of science. Its origins are many and complex, and it is possible here to focus on only one, that associated with the German philosopher Immanuel Kant. Kant challenged the Newtonian confidence that the scientist can deal directly with subsensible entities such as atoms, the corpuscles of light, or electricity. Instead, Kant insisted, all that the human mind can know is forces. This epistemological axiom freed Kantians from having to conceive of forces as embodied in specific and immutable particles. It also placed new emphasis on the space between particles; indeed, if one eliminated the particles entirely, there remained only space containing forces. From these two considerations were to come powerful arguments, first, for the transformations and conservation of forces and, second, for field theory as a representation of reality. What makes this point of view Romantic is that the idea of a network of forces in space tied the cosmos into a unity in which all forces were related to all others, so that the universe took on the aspect of a cosmic organism. The whole was greater than the sum of all its parts, and the way to truth was contemplation of the whole, not analysis.