In 1879, Dow and various tycoons, geologists, lawmakers, and investors set out on a four-day train trip to reach Colorado. Dow learned a great deal about the world of money on that journey as the men smoked cigars, played cards, and swapped stories. He interviewed many highly successful financiers and heard what sort of information the investors on Wall Street needed to make money. The businessmen seemed to like and trust Dow, knowing that he would quote them accurately and keep a confidence. Dow wrote nine "Leadville Letters" based on his experiences there. He described the Rocky Mountains, the mining companies, and the boomtown's gambling, saloons, and dance halls. He also wrote of raw capitalism and the information that drove investments, turning people into millionaires in a moment. He described the disappearance of the individual mine-owners and the financiers who underwrote shares in large mining consortiums. In his last letter, Dow warned, "Mining securities are not the thing for widows and orphans or country clergymen, or unworldly people of any kind to own. But for a businessman, who must take risks in order to make money; who will buy nothing without careful, thorough investigation; and who will not risk more than he is able to lose, there is no other investment in the market today as tempting as mining stock."