Andrew Carnegie (1835-1919), Scottish-American industrialist. Carnegie worked initially as a boy in the cotton industry and as a telegrapher for a railroad company. As he was promoted he invested his money in shares and by 1864 was trading in oil. In 1865, he financed iron and steel works used for making bridges. His factories were amongst the first to use the Bessemer process for making steel. By 1899, he controlled about 25% of American steel manufacture and was also involved in mining, railways and shipping. Carnegie shared his wealth, funding various cultural, educational and peace institutions, including over 1700 libraries.