How did Carnegie's early job with the railroads greatly contribute to his success in the steel business?

Carnegie's early work with the railroads contributed to his success in the steel business because of relationships and capital (money) that he acquired throughout this process. Carnegie early in his career made investments and profits from the railroad industry. After his early successes in the railroad industry he used these investments and also connections he made in this business to develop a new business venture in the steel industry. This became highly lucrative and Carnegie went on to make hundreds of millions of dollars in the steel industry.