Oil became a valuable resource in Ohio when significant quantities were discovered in Lima in 1885, bringing an economic boom to Lima and northwest Ohio. News of the Lima oil field spread and attracted John D. Rockefeller, co-founder of Standard Oil, who invested heavily in Lima crude despite its high sulfur content and foul odor. Storage tanks and pipelines for the crude sprang up rapidly, and Rockefeller sent Standard's chief refining specialist, J. W. Van Dyke, to Lima to construct and manage the new Solar Refinery. Working with German chemist Herman Frasch, Van Dyke perfected a technique to desulphurize the crude and turn it into quality kerosene and fuel oil. From 1886 to 1900, the Lima Oil Field was the leading producer of oil in the world, yielding 190 million barrels. Lima also became a significant pipeline center, and by 1893 a trunk line carried oil to light the buildings at the Chicago World's Fair. Although the Sherman Anti-Trust Act of 1890 eventually led to the 1911 break up of Standard Oil's monopoly, the company continued to play an important role in Ohio. In 2000, Ohio had more than 62,000 active oil wells and produced 6.5 million barrels of crude, and although the current Lima refinery imports its oil via pipeline, the complex remains the oldest, continuously operated oil refinery site in Ohio.