The benefits that we take for granted, such as clean water and working sanitation systems, plentiful food, and electronic conveniences.
The history of engineering has been directed at such problems, and we are the beneficiaries of their solutions as well as the inheritors of unforeseen new problems that engineering solutions have created.
The success or failure of engineering endeavors often has less to do with technical issues than with nontechnical issues including economics, social conventions, and luck.
definitions of engineering emphasize the application of knowledge of science and math to develop useful objects, products, structures, and so forth.
Medieval cathedral builders can be considered as engineers even though their scientific understanding of forces and loads in structures was limited.
Engineers - one who constructs military engines; military engines were devices such as catapults as well as fortifications, roadways, and bridges.
Expanded to mean one who invents or designs.
2: Historical Themes
Engineering requires creativity and judgment in applying math and science to solve problems.
significant effort was often required to make things work.
Problems are usually solved by teams working within the broader societal structures. For example, most of history’s large construction projects such as the pyramids in ancient Egypt, the great cathedrals in Medieval Europe, or the large dams in the western United States required extensive materials, labor, and other resources.
Governments have often provided resources for engineering projects, and have spurred development of new technologies, including accurate clocks for measuring longitude, early computers, military aircraft, and rockets and technology for space travel.
Governments have influenced technology through laws and policies. Some laws may be implemented to protect public safety; for example, explosions of boilers in steam engines in the late 1800s led to government regulation and safety standards.
Patents represent another way in which governments use laws to influence technology; a patent gives its holder legal rights to stop others from using a particular technique or design.
Engineering progress provides new human capabilities, which in turn increase engineering capabilities. Many technological advancements provide a foundation for further technological advancements. For example, the development of affordable printing methods (including movable type and the mechanical printing press) led to wider availability of books and promoted literacy; this in turn led to wide dissemination of scientific knowledge which formed the foundation of the Industrial Revolution. As another example, the development of computers enabled the subsequent development of computer-aided design software, which is now used to create even more powerful computers.
Engineering produces both intended and desirable consequences as well as unintended and undesirable consequences. For example, the development of trucks and cars has allowed people and goods to travel widely. However, these vehicles are a major source of air pollution, particularly in developing nations, and these vehicles have made urban sprawl a major issue in most major American metropolises. In today’s world, engineered systems have become incredibly complex, and no one individual can understand all of the ramifications of a complex technical system; this complexity generates uncertainty, which can lead to problems and even disasters, particularly when circumstances or consequences cannot be foreseen by the engineers developing a system.
As you read this chapter, see if you can identify examples of each of these themes.
6.5: The Industrial Revolution
The Industrial Revolution occupied the eighteenth and nineteenth centuries.
A primary aspect of the Industrial Revolution is that machine power replaced human and animal power.
Developments of an accurate clock to measure longitude
Steam engines
Automatic machinery for creating textile
Mechanical printing
Steam-powered transportation
The simplest method of determining longitude is to determine the difference between the time at one’s current location and the time at a known location (typically the prime meridian at Greenwich, England). In order to know the time at Greenwich, one must have a very accurate clock that has been set to Greenwich’s time.
John Harrison (1693–1776) was an English clockmaker, who in a series of five designs developed a clock accurate
His clock had to maintain accurate time on long sea voyages on which temperature, atmospheric pressure, and humidity varied dramatically.
One was called a grasshopper escapement. The escapement is the mechanism that converts the swing of the pendulum into the turning of a gear by a specific amount for each swing; the gear in turn drives the mechanism that moves the clock hands.
Steam Engines
One of the major technological changes that began during the Industrial Revolution was replacing water, wind, human, and animal power by machine power.
The steam engine was originally developed to pump water out of coal and metal mines.
Steam engines were also used to provide power for textile mills and other factories;
The first commercially steam engine was developed by Thomas Newcomen (1664–1729) in England.
Had a large cylinder in which a piston moved up and down.
Steam introduced into cylinder and created a vacuum.
Pressure on the other side of the piston caused the piston to move.
Piston connected to rocker arm.
Movement of rocker arm used to drive the pump.
James Watt (1736–1819) developed an improved version of the steam engine. His engine , requiring only a quarter as much fuel, and thus was much less costly to run.
The metric unit of power is named after Watt. Thus, one can talk about a “100 watt” lightbulb as a bulb that uses 100 watts of (electric) power.
Textiles
Industrial Revolution, cloth made in factories using machinery powered by steam engines.
Textiles involve two processes.
Spinning, is the manufacturing of thread from fibers like cotton
Weaving the thread into fabric.
In 1769, Richard Arkwright (1733–1792) patented the water frame, a machine that used water power to spin cotton into thread.
water frame in cotton mill; this created one of the first factories that was constructed to house machinery;
One of the most famous American engineering developments associated with textiles was the invention of the cotton gin by the inventor Eli Whitney (1765–1825) in 1792; the cotton gin is a machine that removes seeds from cotton after it is picked. Figure 13 shows the internal machinery of Whitney’s cotton gin.
Mechanical Printing
The process of setting type remained largely unchanged for 400 years after 1480. Letter molds were cast by hand, and these molds were hand assembled into rows and pages of text.
The industrial revolution in the nineteenth century brought changes, first to the printing processes, and then to typesetting. Friedrich Koenig (1774–1833) invented a steam-powered printing press; This press could make 1100 impressions per hour.
Steam Powered Transportation
The steam engine had a revolutionary effect on mining and manufacturing.
Robert Fulton (1765–1815) was the first to successfully develop a steamship in the United States. In 1807, he completed construction of 146 foot-long steamboat. The boat was powered by a 24 horse-power Boulton and Watt engine. It used wood for fuel. The boat transported passengers and cargo between New York City and Albany, New York, much more quickly than a sail-powered boat could.
As important as was the development of steam-powered ships, the development of steam-powered railroads had a much greater effect on the United States economy in the later half of the nineteenth century. Trains came to be the dominant mode of transport during this time. The corporations that built and operated the railroad system were the largest corporations during this period and created significant wealth for their owners.
The first rail locomotive was built in 1803 in England by Richard Trevithick (1771–1833).
The first commercial railroad in the United States was the Baltimore and Ohio Company; in 1830, it opened the first 13 miles of track in the United States. By 1860, there was over 30,000 miles of track in the United States.
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