The document discusses the rise of steel and oil industries in the late 1800s led by Andrew Carnegie and John D. Rockefeller. Carnegie built successful steel mills in Pittsburgh in the 1860s-1870s that produced steel at lower costs than competitors. He consolidated other steel mills under his company, which became the largest steel producer in the U.S. Rockefeller set up an oil refinery in Cleveland in 1863 and was able to buy out other refineries, consolidating them into Standard Oil Company in 1870. Both Carnegie and Rockefeller achieved great wealth and business success through lowering costs and consolidating their respective industries under their large companies.