Increased output stemmed initially from changes in the organization of work that turned independent artisans into wage laborers. Traditionally, New England shoemakers had turned leather hides into finished shoes and boots in small wooden shacks called “ten-footers,” where they worked at their own pace. During the 1820s and 1830s, merchants in Lynn, Massachusetts, destroyed the businesses of these artisans by introducing an outwork system and a division of labor. The merchants hired semiskilled journeymen and set them up in large shops cutting leather into soles and uppers. They sent out the upper sections to rural Massachusetts towns, where women binders sewed in fabric linings. The manufacturers then had other journeymen attach the uppers to the soles and return the shoes to the central shop for inspection, packing, and sale. This more efficient system increased output and cut the price of shoes and boots, even as it turned employers into powerful “shoe bosses” and eroded workers’ wages and independence.

For products not suited to the outwork system, manufacturers created the modern factory, which concentrated production under one roof. For example, in the 1830s, Cincinnati merchants built large slaughterhouses that processed thousands of hogs every month. The technology remained simple, but a division of labor increased output. As a system of overhead rails moved the hog carcasses along a “disassembly” line, one worker split the animals, another removed the organs, and others trimmed the carcasses into pieces. Packers then stuffed the pork into barrels and salted it to prevent spoilage. Reported landscape architect and journalist Frederick Law Olmsted:

We entered an immense low-ceiling room and followed a vista of dead swine, upon their backs, their paws stretching mutely toward heaven. Walking down to the vanishing point, we found there a sort of human chopping-machine where the hogs were converted into commercial pork. … Plump falls the hog upon the table, chop, chop; chop, chop; chop, chop, fall the cleavers. … We took out our watches and counted thirty-five seconds, from the moment when one hog touched the table until the next occupied its place.

The Cincinnati system was so efficient — processing sixty hogs an hour — that by the 1840s the city was known as “Porkopolis.” By 1850, factories were slaughtering 334,000 hogs a year, and 400,000 by 1860.

Other factories boasted impressive new technology. In 1782, Oliver Evans, a prolific Delaware inventor, built a highly automated flour mill driven by water power. His machinery lifted the wheat to the top of the mill, cleaned the grain as it fell into hoppers, ground it into flour, and then cooled the flour as it was funneled into barrels. Evans’s factory, remarked one observer, “was as full of machinery as the case of a watch.” It needed only six men to mill 100,000 bushels of wheat a year — perhaps ten times as much as they could grind in a traditional mill.

By the 1830s, a new “mineral-based economy” of coal and metal began to emerge. Manufacturers increasingly ran their machinery with coal-burning stationary steam engines rather than with water power. And they now fabricated metal products — iron, brass, copper, and tinplate (tin-coated rolled iron) — as well as pork, leather, wool, cotton, and other agricultural goods. In Chicago, Cyrus McCormick used steam-driven machines to make parts for farm reapers, which workers assembled on a conveyor belt. In Hartford, Connecticut, Samuel Colt built an assembly line to produce his invention, the six-shooter revolver. Other New England artisans designed machines that fabricated tinplate into pails, pans, pots, and dozens of other inexpensive and useful household items. These advances in technology and factory organization alarmed British observers: “The contriving and making of machinery has become so common in this country … [that] it is to be feared that American manufacturers will become exporters not only to foreign countries, but even to England.”