Civil Engineering

Civil engineering, like military engineering, emerged in large part from the employments of Renaissance architects. Many Renaissance cities and regional princes engaged an architect-engineer to oversee the construction of all public works, including defensive structures, bridges, and maintenance of roads and waterways. Well into the eighteenth century, a number of engineers maintained versatile skills in both military and civil engineering, although men of more specialized backgrounds, such as surveyors, millwrights, and drainage engineers, always added expertise in the construction of public works and often fashioned themselves more broadly as engineers. Mathematicians, too, consulted on engineering works and helped develop the relationship between engineering and the emerging sciences of mechanics and hydrology. The rise of absolutism combined with growing capital interests to fund a broad range of city-planning, communication, and, above all, water-management programs. Civil engineers were those experts who rose to the challenges and the perquisites these projects offered.

Cities and Villas

The vision of the Renaissance city developed out of new conceptions of the role cities played and an idealized notion of classical urbanism. Building programs to reshape major capitals or plan new military strongholds created cityscapes that demonstrated the power of the rulers, but also served pedestrian traffic, the easy transport of goods (or munitions), water-supply needs, and public theaters and hospitals. The work of Domenico Fontana (1543–1607) for Sixtus V is emblematic: Fontana not only designed new, more convenient, traffic patterns for Rome, but he was involved in the vaulting of St. Peter's cupola and is best known for his direction of the removal of a giant Egyptian obelisk from the site of the Circus Maximus and its reerection in the center of St. Peter's piazza. The latter was itself a theatrical technological feat that involved massive scaffolding and numerous windlasses, tackles, and pulleys. It drew a huge audience of spectators, reportedly hushed under threat of death so that workers could hear the bell prompts.

Structural Engineering

Expertise with materials was largely a tacit knowledge among Renaissance architects and engineers. The astounding heights achieved by the domes and basilicas of the period tested artisanal acumen in the analysis of tensional stress and outward thrust. Filippo Brunelleschi's (1377–1446) pioneering octagonal duomo atop Santa Maria dei Fiori in Florence featured a double-shelled dome, tapered walls that distributed stress to the thicker walls at the base, and a wooden chain that fortified the structure precisely at the point where tensional strain was greatest. A number of engineers consulted on the challenges posed by the even larger and higher circular dome of St. Peter's in Rome, finally completed under Michelangelo Buonarroti (1475–1564). In designing St. Paul's Cathedral in London, Christopher Wren (1632–1723) drew on structural ideas provided by the Royal Society's curator, Robert Hooke (1635–1703). By the beginning of the eighteenth century, rules for the proportioning of a masonry dome were available through the Swiss architect Carlo Fontana (1634–1714), and an easy geometrical construction for determining the thickness of abutments known as "Blondel's Rule" widely applied. The French mathematician Philippe de la Hire (1640–1718) investigated dome equilibrium from the point of view of theoretical statics. Three mathematicians, hired to analyze the cracks in St. Peter's dome in 1742–1743, partially employed de la Hire's work, but it seems to have been little utilized by practicing engineers.

Arched bridges were also a favorite form for experimentation by early modern engineers. Their construction was detailed by technical experts from Leon Battista Alberti (1404–1472) to Jean Rodolphe Perronet (1708–1794). Some of the most acclaimed examples of early modern engineering are bridges, such as the Rialto Bridge in Venice (Antonio da Ponte, begun 1588), Santa Trinità in Florence (Bartolomeo Ammannati, begun 1567), and the Pont Neuf in Paris (Jacques Androuet and Guillaume Marchand, begun 1578).

Galileo Galilei (1564–1642), himself trained as a military engineer, attempted to address some of the problems posed by structural engineering mathematically in the first half of his Discourses on Two New Sciences, devoted to material strength. The "new" science presented ways of determining the tensile strength of beams and ways of proportioning machines in larger scales. Galileo also discussed the subject of centers of gravity, a subject that had been developed by mathematicians Luca Valerio (1552–1618) and Federico Commandino (1509–1575), as a key to determining the equilibrium of rigid systems. This approach, rooted both in engineering practice and the Archimedean revival so influential to Renaissance engineers, contrasted dramatically with the prevalent Aristotelian approach to materials.

Water supply and fountains. Water was supplied to city residents through aqueducts or pipes. Raising enough water from nearby river sources with pumps was a constant occupation of engineers. One of the most ingenious pumping stations was constructed in 1602 by the Flemish hydraulic engineer Jean Lintlaer, whose water-wheel-driven pump, constructed under the Pont Neuf, could rise and fall with the level of the river.

Lintlaer had been hired by Henry IV (ruled 1589–1610) not only on behalf of Paris, but because the king wanted to improve his gardens. The baroque fountains that engineers designed for the gardens of very wealthy houses across Europe were largely inspired by the work of the ancient engineer Hero of Alexandria. Hero had used the natural flow of water, the effects of air pressure and steam, and the creation of a vacuum to achieve delightful effects, such as the playing of music or operation of mechanical birds. Hero's Pneumatica was translated numerous times between 1575 and 1700, many vernacular editions brought out by engineers. The book not only inspired technological marvels, but set out a newly revived matter theory. Hero maintained that the air was elastic, and was composed of tiny bits of matter separated by vacua, a theory discounted by traditional Aristotelians.

Water Management

The professions of water management assumed ever greater attention in the early modern period. Hydraulic engineering was necessary not only to raise water for drinking and fountains, but to drain and reclaim wetlands, dredge ports and harbors, build canals, and turn mills for industry. In Venice, a sea-empire into which several rivers flowed, nine out of ten patents were requested by inventors of machines that could control or utilize water. The various demands on waterways could also conflict. Too many mills constructed on a river would hinder commercial traffic, or even drinking water delivery. A river diverted to serve the needs of one town might render another town's waterways unnavigable.

The leaders in hydraulic engineering were the Dutch, who had developed their expertise through long experience maintaining their below-sea-level landscape with dykes, dredging machines, and canals. Regarding the interrelation of hydraulic works and Dutch government, the English poet Andrew Marvel quipped, "To make a bank, was a great plot of state/Invent a shov'l and be a Magistrate." Indeed, administrative skills were often an indispensable requisite for engineers who directed the huge labor force that large water management schemes demanded.

Land reclamation. Europeans began to drain the wetlands of alluvial plains beginning at least in the twelfth century. In the sixteenth century, the desire to create productive land from the swampy river valleys was translated into capital investment. Olivier de Serres (1539–1619) gave full attention to the conversion of marshlands into arable rents in his Théâtre d'Agriculture. Sixteenth- and seventeenth-century land improvement schemes were carried out from Andalusia through Italy, the Languedoc, the lower Rhône, and the fens of England. The latter was a favorite project of James I (ruled 1603–1625) for which he hired the Dutch engineer Cornelius Vermuyden (1595?–1683). The reclaimed land fell to the control of regional noblemen and investors, and head engineers were sometimes given grants from them.

Ports, rivers, and canals. Rivers and tidal ports prone to silting required periodic dredging. This was usually accomplished with bucket or scraper dredgers. Ports often needed seawalls or the installation of locks. Salvage operations were also a matter of import to the state and to entrepreneurs, as wrecked ships blocked harbors. Sometimes, inventive but ultimately inefficacious schemes were conducted, such as the attempt of Bartolomeo Campi (1525–1573) to raise a sunken ship in the Venetian lagoon with a machine built on two caissons, on Archimedean hydrostatic principles suggested by the mathematician Niccolò Tartaglia (1500–1557). However, the use of diving bells and diving suits, such as those developed by the mathematicians Giovanni Alfonso Borelli (1608–1679) and Edmond Halley (1656–1742), were the more promising means of removing wreckage.

Rivers and their tributaries were constantly diverted, channeled, or dammed in order to irrigate land, avoid flood, or improve navigation. Engineers reinforced banks with piers and the planting of trees and straightened and deepened numerous tributaries. The greatest boon to intracontinental navigation was the development of canal locks.

The invention of the lock was of signal importance to commerce and communication. The construction of intercity turnpikes and well-drained roads did not accelerate until the second half of the eighteenth century. Systems of canals, however, greatly extended alluvial navigation beyond the paths of naturally navigable rivers, and made possible commercial transport between many more cities. Canal waters were also employed to turn the water wheels that powered numerous mills.

While single gates had been employed in regulating water flow, the first lock, with gates at either end of a short section of the canal, appears to have been constructed by Bertola da Novate in the mid 1450s. Bertola, commissioned by the Duke of Milan, Francesco Sforza (ruled 1450–1466), to enlarge the Berguardo Canal, devised the scheme by which boats could ascend or descend the elevation of the waterway in a step-wise way by lifting one gate to fill or empty to the level of the subsequent section of canal. In seventeenth-century Netherlands, where canals had defined the landscape since the Middle Ages, new intercity canals were dug that carried passenger traffic on horse-drawn boats. England almost doubled its river navigation in the second half of the century, from 685 miles to 1160 miles. In France, the ambitious project to connect the Mediterranean with the Atlantic by canal, originally promoted by Leonardo da Vinci in the service of Francis I, was half completed with the Canal du Midi in 1681. Beginning in 1642, the foodstuffs of the Loire Valley could be carried to Paris via a canal that included thirty-five locks, and featured a seven-rise staircase of consecutive locks. The fortifications chief, Sébastien le Prestre de Vauban (1633–1707), extended the canal system through Belgium.

Hydraulics and mathematicians. Attempts to systematize the artisanal knowledge of hydraulic engineering within a more learned framework were available by the seventeenth centuries in the work of Alvise Cornaro (1484–1566) and Simon Stevin (1548–1620). Although Stevin was a preeminent mathematician, his hydraulics did not significantly depart from contemporary engineering practices. The work of Galileo's pupil Benedetto Castelli (1577–1644), in response to Papal plans to (re)divert the Reno into the Po flowing past Ferrara, extended the geometrical study of motion to waters. While Renaissance engineers like Leonardo had grappled with questions of water velocity, Castelli carved out new territory in his 1628 On the Measurement of Running Waters (Della misura dell'acque correnti). Castelli articulated the law of constant flow, that a river discharges equal quantities of water in equal times, regardless of the size of the cross-section. While this work had little direct effect on practice, the science of fluids was studied intensively over the next century. Fluid mechanics was developed experimentally by the French physicist Edme Mariotte (1620–1684), and the mathematician Daniel Bernoulli (1700–1782) formulated the relationship between the density of fluid in a pipe, its speed and pressure. By the eighteenth century, figures such as the mathematical professor and hydraulic engineer/government administrator Giovanni Poleni (1683–1761) were not rare.

Industrial Machines

Early modern engineers constantly designed and redesigned the wheeled machines that lifted stones for building; pumps that drained mines and swamps and raised water for drinking or ornamental fountains; and a vast array of machines that milled wheat, crushed minerals, lifted hammers, beat cloth, and operated the bellows of the new iron blast furnaces. Until the employment of the steam engine in the eighteenth century, the power of these machines was either a water wheel, a human-turned treadmill, winch, capstan, or crank, or an animal-turned device such as the horse whim. The cam, which translated rotational motion into vertical motion, was greatly developed by sixteenth-century engineers and was of huge industrial import. Printed machine books produced by Agostino Ramelli (1531–c. 1600), Jacques Besson (1540–1576), and Vittorio Zonca (b. c. 1580) demonstrate how combinations of toothed wheels, worm gears, crown gears, and lanterns might redirect motion in various ways. The treadmill that powered a sixteenth-century crane employed several men running on the inside of a huge wheel; due to gearing and other improvements, eighteenth-century cranes were smaller and could be turned externally with a crank.

With the mutually reinforcing developments of mining, metallurgy, and steam engines, the mechanical engineer had, literally, to retool. The new steam engines were first used in the drainage of mines; the new product of cast iron found one of its premier uses in the cylinders used on the steam engine. While engineers had increasingly employed metal in eighteenth-century machines, its wide adoption in the final years of the eighteenth century not only added strength, but also made precision, industrial tooling possible. The circle around the steam-engine moguls James Watt (1736–1819) and Matthew Boulton (1728–1809) procured watchmakers and other artisans skilled in machining gears. With the invention of the industrial lathe in 1716 by Christopher Polhem (1661–1751) of Sweden, its development by Jacques de Vaucanson (1709–1782) and others, and the 1776 cylinder-boring machine of the ironmaster John Wilkinson (1728–1808), it became possible to produce machines that produced machines.

Engineers, Science, and Professionalism

Throughout the early modern period, civil engineers were artisans of more and less learning, or mathematicians of more and less experience. The relationship between the practices of engineering and the new mathematical sciences of mechanics and hydraulics, however, was never unidirectional or static, nor was it easy to generalize. The engineer and machine book author Agostino Ramelli wrote an elaborate preface insisting on the necessity of mathematics as the foundation for machine design. On the other hand, practicing engineers often resisted the advice of mathematicians employed as consultants and sneered at theoreticians. In both cases, the relationship seems rhetorically constructed. Only in the eighteenth century did a more stable professional identity for engineers emerge, as technical education was formally organized and the social role of the technical expert more clearly defined. By that time, the sciences of rational mechanics and hydrology had developed within the framework of engineering problems.

John Smeaton (1724–1792) was the first Englishman to adopt the title "civil engineer." Although he was trained, as were many engineers, as a millwright, Smeaton performed systematic experimentation on the superior efficiency of overshot waterwheels, engaged in investigations regarding Leibnizian and Newtonian mechanics, and advocated a more rigorous technical education. The leaders in the establishment of the latter were the French.

In keeping with the rational systematization of absolutist, Enlightenment France, the Corps de Ponts et Chaussées was founded in 1719 to organize the network of roads and waterways throughout the country. Members of the corps tested the bending of various materials and invented machines for compression tests on stone and mortar; Henri de Pitot (1695–1771) invented the Pitot tube, by which the velocity of a current could be taken. The corps also founded a school. Cadets would have available to them the textbooks of Bernard Forest de Belidor (1697–1761), books reprinted so often that the copper plates wore out and had to be reengraved in the early nineteenth century. There was nothing new or cutting-edge in these handbooks, but they offered both traditional guidelines of practice and the possibility of applying static and dynamic theorems to practical problems. The French engineering organizations were the apotheosis and production line for engineers who could combine knowledge, machines, and the organization of human labor in order to fulfill corporate demands for huge undertakings.

Automobile

In 1908 Henry Ford began production of the Model T automobile. Based on his original Model A design first manufactured in 1903, the Model T took five years to develop. Its creation inaugurated what we know today as the mass production assembly line. This revolutionary idea was based on the concept of simply assembling interchangeable component parts. Prior to this time, coaches and buggies had been hand-built in small numbers by specialized craftspeople who rarely duplicated any particular unit. Ford's innovative design reduced the number of parts needed as well as the number of skilled fitters who had always formed the bulk of the assembly operation, giving Ford a tremendous advantage over his competition.

Ford's first venture into automobile assembly with the Model A involved setting up assembly stands on which the whole vehicle was built, usually by a single assembler who fit an entire section of the car together in one place. This person performed the same activity over and over at his stationary assembly stand. To provide for more efficiency, Ford had parts delivered as needed to each work station. In this way each assembly fitter took about 8.5 hours to complete his assembly task. By the time the Model T was being developed Ford had decided to use multiple assembly stands with assemblers moving from stand to stand, each performing a specific function. This process reduced the assembly time for each fitter from 8.5 hours to a mere 2.5 minutes by rendering each worker completely familiar with a specific task.

Ford soon recognized that walking from stand to stand wasted time and created jam-ups in the production process as faster workers overtook slower ones. In Detroit in 1913, he solved this problem by introducing the first moving assembly line, a conveyor that moved the vehicle past a stationary assembler. By eliminating the need for workers to move between stations, Ford cut the assembly task for each worker from 2.5 minutes to just under 2 minutes; the moving assembly conveyor could now pace the stationary worker. The first conveyor line consisted of metal strips to which the vehicle's wheels were attached. The metal strips were attached to a belt that rolled the length of the factory and then, beneath the floor, returned to the beginning area. This reduction in the amount of human effort required to assemble an automobile caught the attention of automobile assemblers throughout the world. Ford's mass production drove the automobile industry for nearly five decades and was eventually adopted by almost every other industrial manufacturer. Although technological advancements have enabled many improvements to modern day automobile assembly operations, the basic concept of stationary workers installing parts on a vehicle as it passes their work stations has not changed drastically over the years.

Raw Materials

Although the bulk of an automobile is virgin steel, petroleum-based products (plastics and vinyls) have come to represent an increasingly large percentage of automotive components. The light-weight materials derived from petroleum have helped to lighten some models by as much as thirty percent. As the price of fossil fuels continues to rise, the preference for lighter, more fuel efficient vehicles will become more pronounced.

Design

Introducing a new model of automobile generally takes three to five years from inception to assembly. Ideas for new models are developed to respond to unmet pubic needs and preferences. Trying to predict what the public will want to drive in five years is no small feat, yet automobile companies have successfully designed automobiles that fit public tastes. With the help of computer-aided design equipment, designers develop basic concept drawings that help them visualize the proposed vehicle's appearance. Based on this simulation, they then construct clay models that can be studied by styling experts familiar with what the public is likely to accept. Aerodynamic engineers also review the models, studying air-flow parameters and doing feasibility studies on crash tests. Only after all models have been reviewed and accepted are tool designers permitted to begin building the tools that will manufacture the component parts of the new model.

The Manufacturing
Process

Components

* The automobile assembly plant represents only the final phase in the process of manufacturing an automobile, for it is here that the components supplied by more than 4,000 outside suppliers, including company-owned parts suppliers, are brought together for assembly, usually by truck or railroad. Those parts that will be used in the chassis are delivered to one area, while those that will comprise the body are unloaded at another.

Chassis

* The typical car or truck is constructed from the ground up (and out). The frame forms the base on which the body rests and from which all subsequent assembly components follow. The frame is placed on the assembly line and clamped to the conveyer to prevent shifting as it moves down the line. From here the automobile frame moves to component assembly areas where complete front and rear suspensions, gas tanks, rear axles and drive shafts, gear boxes, steering box components, wheel drums, and braking systems are sequentially installed.
* An off-line operation at this stage of production mates the vehicle's engine with its transmission. Workers use robotic arms to install these heavy components inside the engine compartment of the frame. After the engine and transmission are installed, a worker attaches the radiator, and another bolts it into place. Because of the nature of these heavy component parts, articulating robots perform all of the lift and carry operations while assemblers using pneumatic wrenches bolt component pieces in place. Careful ergonomic studies of every assembly task have provided assembly workers with the safest and most efficient tools available.

Body

* Generally, the floor pan is the largest body component to which a multitude of panels and braces will subsequently be either welded or bolted. As it moves down the assembly line, held in place by clamping fixtures, the shell of the vehicle is built. First, the left and right quarter panels are robotically disengaged from pre-staged shipping containers and placed onto the floor pan, where they are stabilized with positioning fixtures and welded.
* The front and rear door pillars, roof, and body side panels are assembled in the same fashion. The shell of the automobile assembled in this section of the process lends itself to the use of robots because articulating arms can easily introduce various component braces and panels to the floor pan and perform a high number of weld operations in a time frame and with a degree of accuracy no human workers could ever approach. Robots can pick and load 200-pound (90.8 kilograms) roof panels and place them precisely in the proper weld position with tolerance variations held to within .001 of an inch. Moreover, robots can also tolerate the smoke, weld flashes, and gases created during this phase of production.
* As the body moves from the isolated weld area of the assembly line, subsequent body components including fully assembled doors, deck lids, hood panel, fenders, trunk lid, and bumper reinforcements are installed. Although robots help workers place these components onto the body shell, the workers provide the proper fit for most of the bolt-on functional parts using pneumatically assisted tools.

Paint

* Prior to painting, the body must pass through a rigorous inspection process, the body in white operation. The shell of the vehicle passes through a brightly lit white room where it is fully wiped down by visual inspectors using cloths soaked in hi-light oil. Under the lights, this oil allows inspectors to see any defects in the sheet metal body panels. Dings, dents, and any other defects are repaired right on the line by skilled body repairmen. After the shell has been fully inspected and repaired, the assembly conveyor carries it through a cleaning station where it is immersed and cleaned of all residual oil, dirt, and contaminants.
* As the shell exits the cleaning station it goes through a drying booth and then through an undercoat dip—an electrostatically charged bath of undercoat paint (called the E-coat) that covers every nook and cranny of the body shell, both inside and out, with primer. This coat acts as a substrate surface to which the top coat of colored paint adheres.
* After the E-coat bath, the shell is again dried in a booth as it proceeds on to the final paint operation. In most automobile assembly plants today, vehicle bodies are spray-painted by robots that have been programmed to apply the exact amounts of paint to just the right areas for just the right length of time. Considerable research and programming has gone into the dynamics of robotic painting in order to ensure the fine "wet" finishes we have come to expect. Our robotic painters have come a long way since Ford's first Model Ts, which were painted by hand with a brush.
* Once the shell has been fully covered 1 V with a base coat of color paint and a clear top coat, the conveyor transfers the bodies through baking ovens where the paint is cured at temperatures exceeding 275 degrees Fahrenheit (135 degrees Celsius). After the shell leaves the paint area it is ready for interior assembly.

Interior assembly

* The painted shell proceeds through the interior assembly area where workers assemble all of the instrumentation and wiring systems, dash panels, interior lights, seats, door and trim panels, headliners, radios, speakers, all glass except the automobile windshield, steering column and wheel, body weatherstrips, vinyl tops, brake and gas pedals, carpeting, and front and rear bumper fascias.
* Next, robots equipped with suction cups remove the windshield from a shipping container, apply a bead of urethane sealer to the perimeter of the glass, and then place it into the body windshield frame. Robots also pick seats and trim panels and transport them to the vehicle for the ease and efficiency of the assembly operator. After passing through this section the shell is given a water test to ensure the proper fit of door panels, glass, and weatherstripping. It is now ready to mate with the chassis.

Mate

* The chassis assembly conveyor and the body shell conveyor meet at this stage of production. As the chassis passes the body conveyor the shell is robotically lifted from its conveyor fixtures and placed onto the car frame. Assembly workers, some at ground level and some in work pits beneath the conveyor, bolt the car body to the frame. Once the mating takes place the automobile proceeds down the line to receive final trim components, battery, tires, anti-freeze, and gasoline.
* The vehicle can now be started. From here it is driven to a checkpoint off the line, where its engine is audited, its lights and horn checked, its tires balanced, and its charging system examined. Any defects discovered at this stage require that the car be taken to a central repair area, usually located near the end of the line. A crew of skilled trouble-shooters at this stage analyze and repair all problems. When the vehicle passes final audit it is given a price label and driven to a staging lot where it will await shipment to its destination.

Quality Control

All of the components that go into the automobile are produced at other sites. This means the thousands of component pieces that comprise the car must be manufactured, tested, packaged, and shipped to the assembly plants, often on the same day they will be used. This requires no small amount of planning. To accomplish it, most automobile manufacturers require outside parts vendors to subject their component parts to rigorous testing and inspection audits similar to those used by the assembly plants. In this way the assembly plants can anticipate that the products arriving at their receiving docks are Statistical Process Control (SPC) approved and free from defects.

Once the component parts of the automobile begin to be assembled at the automotive factory, production control specialists can follow the progress of each embryonic automobile by means of its Vehicle Identification Number (VIN), assigned at the start of the production line. In many of the more advanced assembly plants a small radio frequency transponder is attached to the chassis and floor pan. This sending unit carries the VIN information and monitors its progress along the assembly process. Knowing what operations the vehicle has been through, where it is going, and when it should arrive at the next assembly station gives production management personnel the ability to electronically control the manufacturing sequence. Throughout the assembly process quality audit stations keep track of vital information concerning the integrity of various functional components of the vehicle.

This idea comes from a change in quality control ideology over the years. Formerly, quality control was seen as a final inspection process that sought to discover defects only after the vehicle was built. In contrast, today quality is seen as a process built right into the design of the vehicle as well as the assembly process. In this way assembly operators can stop the conveyor if workers find a defect. Corrections can then be made, or supplies checked to determine whether an entire batch of components is bad. Vehicle recalls are costly and manufacturers do everything possible to ensure the integrity of their product before it is shipped to the customer. After the vehicle is assembled a validation process is conducted at the end of the assembly line to verify quality audits from the various inspection points throughout the assembly process. This final audit tests for properly fitting panels; dynamics; squeaks and rattles; functioning electrical components; and engine, chassis, and wheel alignment. In many assembly plants vehicles are periodically pulled from the audit line and given full functional tests. All efforts today are put forth to ensure that quality and reliability are built into the assembled product.

The Future

The development of the electric automobile will owe more to innovative solar and aeronautical engineering and advanced satellite and radar technology than to traditional automotive design and construction. The electric car has no engine, exhaust system, transmission, muffler, radiator, or spark plugs. It will require neither tune-ups nor—truly revolutionary—gasoline. Instead, its power will come from alternating current (AC) electric motors with a brushless design capable of spinning up to 20,000 revolutions/minute. Batteries to power these motors will come from high performance cells capable of generating more than 100 kilowatts of power. And, unlike the lead-acid batteries of the past and present, future batteries will be environmentally safe and recyclable. Integral to the braking system of the vehicle will be a power inverter that converts direct current electricity back into the battery pack system once the accelerator is let off, thus acting as a generator to the battery system even as the car is driven long into the future.

The growth of automobile use and the increasing resistance to road building have made our highway systems both congested and obsolete. But new electronic vehicle technologies that permit cars to navigate around the congestion and even drive themselves may soon become possible. Turning over the operation of our automobiles to computers would mean they would gather information from the roadway about congestion and find the fastest route to their instructed destination, thus making better use of limited highway space. The advent of the electric car will come because of a rare convergence of circumstance and ability. Growing intolerance for pollution combined with extraordinary technological advancements will change the global transportation paradigm that will carry us into the twenty-first century.