Oil Refinery (CTP1)

Oil Refinery is a city improvement in Civilization: Call to Power.
==Effect==
The Oil Refinery increases production in a city by 50%. With its towering distillation columns and miles of winding piping, the complexity of the Refinery underlines its key role in modern society.
== Great Library entry ==
With the first discovery of oil, Civilization obtained a powerful source of energy and raw materials which required processing before use. Raw oil consisted of many different hydrocarbon chains. Chains of different weights possessed radically different properties, as seen in the difference between asphalt and gasoline. To use any of the hydrocarbons, they had to be separated. Enter the Oil Refinery. Though the process was expensive, the resulting gasoline was worth the cost.