The technological and managerial innovations of Thomas Alva Edison (the inventor of electricity) and the industrial leaders Andrew Carnegie (iron and steel) and John D. Rockefeller (oil) proved readily adaptable throughout United States industry, spurring marvels of productivity. Late-nineteenth-century industrialists often discovered that their factories produced more goods than the market could absorb. This was particular true in two kinds of businesses: those that manufactured devices for individual use, such as sewing machines and farm implements, and those that mass-produced consumer goods, such as matches, flour, soap, canned foods, and processed meats. Not surprisingly, these industries were trailblazers in developing advertising and marketing techniques. Strategies for encouraging consumer demand and for differentiating one product from another were an important component of the American post-Civil War industrial transformation. The growth of the flour industry illustrates both the spread of mass production and the emergence of new marketing concepts. In the 1870s the nation's flour mills adopted the most advanced European manufacturing technologies and installed continuous-process machines that graded, cleaned, hulled, and packaged their product in one rapid operation. These companies, however, soon produced more flour than they could see. To sell this excess, the mills thought up new product lines, such as cake flours and breakfast cereals, and sold them using easy-to-remember brand names. Through brand names, trademarks, guarantees, and slogans, manufacturers built demand for their products and won remarkable consumer loyalty. Americans in large numbers bought a brand of soap first made in 1897 in Cincinnati, Ohio, because of the absurd overly precise but impressive pledge that it was "99 and 44/100ths percent pure." In the photographic field, George Eastman in the 1880s developed a paper-based photographic film as an alternate to the bulky, fragile glass plates then in use. Manufacturing a cheap camera for the masses and devising a catchy slogan ("you just press the button, we do the rest"). Eastman introduced a system whereby customers returned the 100-exposure film and the camera to the Rochester, New York, factory. There the film was developed, the camera reloaded, and everything shipped back to the customer – for a charge of ten dollars. In marketing a new technology, Eastman had revolutionized an industry and democratized a visual medium previously confined to a few. By 1900 the chaos of early industrial competition, when thousands of small companies had struggled to enter a national market, had given way to an economy dominated by a few enormous films. An industrial transformation that originated in railroading and expanded to steel and petroleum had spread to every area of United States business, and for those who could not compete in the era's unforgiving economic environment, the cost could be measured in ruined fortunes, bankrupted companies, and shattered dreams. John D. Rockefeller, talking about businesses he wanted to acquire, said he wanted "only the big ones, one those who have already proved they can do a big business. As for the others, unfortunately they will have to die." The cost was high, too, for millions of American workers, immigrant and native born alike. The new industrial order was built on the backs of an army of laborers who were paid subsistence wages and who could be fired on a moment's notice when hard times or new technologies made them expendable. Moreover, industrialization often devastated the environment with pollution in the relentless drive for efficiency and profit. To be sure, this industrial revolution brought social benefits as well, in the form of labor-saving products, lower prices, and advances in transportation and communications. The benefits and liabilities were inextricably interconnected. The sewing machine, for example, created thousands of new factory jobs, made available a wider variety of clothing, and eased the lives of millions of consumers. At the same time, it encouraged greedy entrepreneurs to operate factories in which the poor worked long hours in unhealthy conditions pitifully low wages. Whatever the final balance sheet of social gains and costs, one thing was clear: the United States had forced its way onto the world stage as an industrial nation, and the groundwork had been laid for a new social and economic order in the twentieth century.