Engineering involves the application of energy to material to create something a building, a monument, a network of computers. An applied pursuit, it allowed early builders to use initial discoveries about mechanics and chemistry to create structures that remain standing thousands of years later. Imhotep, who built the Step Pyramid in Saqqara, Egypt, in 2550 B.C., is the first builder recognized by name. Vitruvius’s volume De Architectura, published in Rome in the first century A.D., laid out an extensive array of building methods and materials put to use in the Colosseum and the network of aqueducts. Roman agrimensors, or surveyors, used basic math, plumb lines, levels, and right angles to lay boundaries for what was then the world’s greatest empire.
More than a thousand years later, a high level of applied mathematics and materials science went into the construction of Gothic cathedrals and other structures, as revealed in the sketches by Villard de Honnecourt in France. Then, as now, however, the engineering talent of that day was often diverted from architectural projects to military applications: catapults, siege tools, and other machines of war.
Engineering was traditionally concerned with buildings and public projects like roads, docks, and lighthouses. English engineer John Smeaton apparently coined the term “civil engineer” in 1782, marking new directions for engineering as it began to feel the influence of the scientific and industrial revolutions. New technologies evolved that were capable of unlocking and putting to use the forces of electricity, chemistry, heat, and, ultimately, the atom.
THE GOLDEN GATE BRIDGE of San Francisco, an engineering accomplishment completed in 1937, was an early example of longspan suspension bridges.
It is hard to separate the history of engineering from the history of invention of John Smeaton’s development in the 1750s of a mortar that would set underwater, for example; of the improvements James Watt made in the steam engine at the dawn of the industrial revolution, during the 1770s; of Alexander Graham Bell’s telephone and Thomas Edison’s electric light in the last decades of the 19th century. The 20th century saw numerous inventions and advances added to the list of each discipline, as an understanding of the atom created demand for a generation of nuclear engineers and as the advent of the computer gave rise to a host of new engineering specializations: software programmers, chip designers, and network architects.
Engineering Materials for Strength
Engineering advances continue to make new inroads in the traditional field of building. The advent of synthetic materials has given engineers ever greater leeway, changing certain guiding principles of design.
If early builders sought solidity the wide base of the pyramids or the keystone at the top of an arch as a way to balance a structure ‘ s internal forces, modern engineers have in stead found safety in motion.
Modern bridges are built to allow for the expansion and contraction of materials as temperatures change. Modern skyscrapers rest on layers of rubber and include ball bearings under columns to let the buildings sway and dissipate the effects of high wind and earthquakes. Newly engineered materials, often alloys or combinations of metals manipulated at the molecular level, are now designed with strength and flexibility in mind.