The BOOKPRESS February 2000

The Language of Invention


Francis C. Moon

Hidden in glass-enclosed oak cases within the pallid hallways of Cornell University’s Engineering College rests a set of over 200 small machines known as the Reuleaux Collection of Kinematic Mechanisms Hidden in glass-enclosed oak cases within the pallid hallways of Cornell University’s Engineering College rests a set of over 200 small machines known as the Reuleaux Collection of Kinematic Mechanisms. These beautifully made cast-iron and brass models, built circa 1880, represent 300 years of machine art from the time of Leonardo da Vinci to the last quarter of the l9th century.

For the last half-century thousands of Cornell students have passed by these objects of technical art with little knowledge of their history. Now, like modern archaeologists, scholars are trying to reverse-engineer how these machines were meant to work and to uncover the life and times of the man who created them.

For many in the emerging industrial societies of the 19th century, technology was a benefactor to humankind and its practitioners were seen as heroes. Poets such as Walt Whitman lauded the arrival of the machine:

Thy black cylindrical body, golden brass and silvery steel,
Thy ponderous side-bars, parallel and connecting rods,
gyrating, shuttling at thy sides,
Thy metrical, now welling pant and roar,
now tapering in the distance.
To these intellectual leaders at the fin de siecle, science and humanities were not at odds. Technology was viewed as the culmination of Western culture and philosophy stretching back to the Greeks and the Romans.

Two practical intellectuals who embodied this connection between disciplines were Andrew Dickson White, Cornell University’s first president, and Franz Reuleaux, a German engineering professor who was the first President of the Royal Institute of Technology in Berlin. White built mechanical machines as a boy and became a historian, while Reuleaux designed machines professionally, translated Longfellow’s poem Hiawatha into German, and quoted Goethe in his technical books. Both men were prime movers in the creation of new technical universities, traveled the world as representatives of their relatively new countries, and socialized with the intellectual, business and political leaders of their times. They not only shared in the optimism of the machine age, they helped to create it.

Franz Reuleaux was born in 1829 in a German village near Aachen (Aix-la-Chapelle). His father and grandfather were both engineers and manufacturers of machinery and the new steam engines. Franz received an engineering education at the technical institute at Karlsruhe. After two years he went to the universities of Berlin and Bonn to broaden his knowledge in classical subjects, including philosophy and science. Perhaps it was there that he acquired his love of Goethe, poetry, and his interest in the purity of the German language, a cause he would later champion in the united Germany of the second Reich.

The early death of his father called him back to the family business and the practical profession of engineering. He married Charlotte Overbeck of Antwerp and they had five children in the next dozen years. After publishing two popular books on machine design, Reuleaux was asked to accept a professorship at the new Technical Institute at Zurich. There he took an interest in the design of machines. By the 1860s new inventions and machines were appearing almost monthly—not unlike the blizzard of new software assaulting us today.

Machine design requires the study of thermodynamics, materials, and dynamics (or kinematics, as it was called then). In 1875 Reuleaux published a treatise that revolutionized the kinematic design of mechanisms. His book was quickly translated into French, Italian, and English.

Quoting Goethe, Reuleaux proposed that the real quest for the machine engineer was not the analysis of existing devices, but the discovery of the scientific principles of invention itself: "Everything that we call Invention, discovery in the higher sense, is the ultimate outcome of the original perception of some truth." Thus Reuleaux sought the underlying insights that govern the invention of new machines, not just the scientific laws but the process of thinking: "I have attempted to show that Invention...is Thought,—if we systematize that latter, we have prepared the way for the former." Today this search for systematic thought processes in technology is known as artificial intelligence (AI) and design synthesis. Ultimately, Reuleaux conceded his failure to achieve a coherent system of scientific synthesis, but the scope of his attempts remains impressive, especially considering that he did not have the computer tools that are at the heart of AI today.

Central to Reuleaux’s unique contribution was the creation of a symbolic language to classify machines—a syntax of kinematic devices. In his quest for a grammar of machines Reuleaux built the world’s largest collection of over 800 models. Using his symbolic system along with his models, Reuleaux sought to deconstruct every machine that had been or ever would be invented.

Reuleaux may have had access to the 18th-century compendium titled Theatrum Machinarum Generale that attempted to classify machines by function—mills, pumps, construction devices, etc. At around the same time, the Swedish biologist Linnaeus was constructing a taxonomy for plants and animals using ideas of species, genus, family, orders, and kingdoms. Some of these biological taxonomies were based on physical similarities and some on evolutionary ancestors. At first Reuleaux also tried to classify machines according to their function, such as place-changing machines or form-changing machines, but he switched to a syntax-based methodology, inspired by linguistics rather than biology.

Machines function by channeling energy along certain paths. This focusing of the chaos of molecules and heat into regular motions allows the user of the machine to accomplish useful work. Reuleaux visualized each machine as a chain of kinematic constraints, each determined by the geometric relation between adjacent parts. A piston in a steam engine, for example, is confined to slide back and forth in the cylinder. Each link on a bicycle chain is constrained to rotate about an axis relative to the adjacent link, and so on. The key to distinguishing one machine from another is the sequence of these different linked pairs.

Reuleaux realized that each kinematic pair could be written as a symbol—letters with superscripts and subscripts—and the entire machine could be expressed as a sequence of symbols. By consulting these symbols on a piece of paper Reuleaux believed that someone who had never seen the originals could reconstruct the essential machines, although the dimensions and materials might be different. Though his Machine Age equivalent of the Genome Project was never finished, Reuleaux’s models do represent a kind of visual dictionary of l9th century technology.

In his essay Technology and Civilization, written in 1890, Reuleaux tries to determine the characteristics of technologically developed societies. He rejects racial and religious distinctions, noting the successes of the Chinese and the Arabians centuries earlier, and he points out the acceleration of industrial progress in Japan in the last quarter of the l9th century.

Using the metaphor of the machine, where each component is strictly linked to the next, he reasons that the technical progress of a "learned world" depends on the societal linkages of raw materials, energy, transportation, communication, and education. What Reuleaux calls "Scientific Technology" derives from a society whose members are firmly educated in logic, reason, and the laws of nature. Again Reuleaux quotes Goethe:

According to laws mighty, fixed, eternal,
Must we complete our being’s circle
Like many of his generation, Reuleaux had an almost messianic faith in science and technology: "If we bring lifeless bodies into such circumstances that their working of natural laws answers our purposes, we may permit them instead of this labor to work for living beings." For this to happen, however, requires a belief that the secrets of nature are not forever hidden from human inquiry. Societies whose guiding principles are the mysterious and unknowable, he labeled Naturistic. Societies that understand the forces of nature he called Manganistic, which he claimed is based on a Greek word for an artistic mechanism, manganon. Reuleaux argues that manganistic societies have a powerful advantage over naturistic societies, but (using the example of Japan) any society can enter the world of scientific technology through "learning, learning, learning."

Reuleaux did acknowledge some of the evils of technology, such as the transformation of craftsmen into impersonal cogs of the factory machine. Still he believed these "deficiencies" could be overcome: "Scientific technology has become the bearer of culture, the powerful laborer in the service of civilization and the cultivation of the races of man, and promises for a long future to add a line of greater results than is at present attained."

One cannot understand Reuleaux without looking at the milieu in which he grew up. His birth place Aachen became a part of West Prussia after the defeat of Napoleon in 1814. At the time, Germany was a collection of small kingdoms fending off the two powers of Prussia and Austria. By 1890, Prussia and Bismark had united Germany by force and made Berlin its imperial capital. At the beginning of the l9th century Berlin was no more than a military barracks for the King of Brandenburg; by the end of the century it was a great industrial and cultural center of Europe. In spite of the Prussian suppression of the liberal democratic revolution of 1848, Berlin remained a city with a split personality. Royalists held political power, but there was also a large population of liberals, socialists like Karl Marx, and an assortment of small entrepreneurs and industrialists. Reuleaux clearly identified himself with the latter two groups. Although a German nationalist who believed in a strong role for the State in a modern technical society, he was also an internationalist in his correspondence and travels.

Reuleaux took part in the official World Expositions at Paris (1867), Vienna (1873), Philadelphia (1876), Sidney (1879), and Melbourn (1881). These expositions were no theme parks with ersatz Bavarian beer halls and Swiss chalets; they were competitive events that involved industrial status, espionage, and national pride. At Paris, for example, the French inventor Lenior had expected his new internal combustion engine to win the gold medal. Reuleaux was on the jury and insisted that all the engines be subjected to a fuel efficiency test. As a result, the German engine of Otto and Langen was shown to be far more efficient than the French and was awarded the gold medal.

Reuleaux was the official German ambassador for the Centennial Exposition of 1876 in Philadelphia. But this time his technical judgments were aimed at Germany itself. In his small book published in German, Briefe aus Philadelphia (Letters From Philadelphia), he criticized the German manufactures and exhibits at the Exposition as "billig und schlecht," cheap and shoddy. He lectured the Germans on the need for quality as well as low price. These harsh words were taken very seriously in the new Germany, especially Reuleaux’s emphasis on the role of the State in the promoting of education, industry, and the welfare of the worker.

Reuleaux and Cornell president Andrew D. White may have met at the 1876 Centennial, though Reuleaux’s models were probably not shown there but in another exhibition the same year at the Kensington Museum in London. They may have met again in Berlin while White was the American Minister to Germany in 1879-81. Certainly Reuleaux’s letter to White in 1882 (in English), announcing that the models were ready for delivery to Ithaca, indicates that they had already met. "I only wish I could have the pleasure to open the cases with you and explain the objects at once to you and our friends. They will I am sure, make you impatient for the next series," writes Reuleaux.

Seeing these models today, with their precise craftsmanship and beauty of design, it is easy to think of Reuleaux as a clever mechanic rather than the theoretician that he was. Yet the various motions described by these mechanisms represent mathematical models of geometric figures: cycloids, hypocycloids, peritrochoids—terms now almost forgotten by mathematicians and engineers. Reuleaux created his models to demonstrate the logical laws of mechanics and motion. Today, many who visit the Cornell collection see them as works of art, even as kinetic sculptures.

Francis C. Moon is the Joseph Ford Professor of Mechanical Engineering at Cornell University.

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