(p. 78) Carnegie, having satisfied himself that there was oil in the ground and a way to ship it to Pittsburgh, agreed to invest in Coleman’s oil company. While other prospectors fantasized only about the liquid gold that lay deep in the ground, Coleman and Carnegie believed that in the not too distant future the wells would run dry. To prepare for that day and turn it to their advantage, Coleman proposed–and Carnegie agreed–to construct a man-made lake, pump the oil from their wells into it, and leave it there until the supply dwindled and prices rose. Coleman and Carnegie waited for the region to run out of oil while their lake leaked thousands of barrels daily. Unable to find any efficient way to store the oil, they had to sell it on the open market.
Source:
Nasaw, David. Andrew Carnegie. New York: Penguin Press, 2006.
(Note: the pagination of the hardback and paperback editions of Nasaw’s book are the same.)