Until the Industrial Revolution there were only two kinds of engineers.

The military engineer built such things as fortifications, catapults, and, later, cannons.

The civil engineer built bridges, harbors, aqueducts, buildings, and other structures.

During the early 19th cent. in England mechanical engineering developed as a separate field to provide manufacturing machines and the engines to power them.

The first British professional society of civil engineers was formed in 1818; that for mechanical engineers followed in 1847. In the United States, the order of growth of the different branches of engineering, measured by the date a professional society was formed, is civil engineering (1852), mining and metallurgical engineering (1871), mechanical engineering (1880), electrical engineering (1884), and chemical engineering (1908). Aeronautical engineering, industrial engineering, and genetic engineering are more modern developments.

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