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Affiliated with the Local History Network of the State Historical Society of Iowa, and the Iowa Museum Association.
SOCONY MOBILE OIL COMPANY INC.
SOCONY MOBILE OIL COMPANY INC. Vacuum Oil was founded in 1866 by Matthew Ewing and Hiram Bond Everest, of Rochester, New York. Lubrication oil was an accidental discovery while attempting to distill kerosene. Everest noted the residue from the extraction was suitable as a lubricant. Soon after, the product became popular for use in steam engines and internal-combustion engines. Ewing sold his interest to Everest, who carried on the company. Vacuum was bought by Standard Oil in 1879.
Standard Oil originated the Mobil trademark in 1899 (as "Mobilgas;" "Mobiloil" came later). When Standard Oil was broken up in 1911 due to the Sherman Antitrust Act, Vacuum became an independent company again.
Vacuum Oil and Standard Oil of New York (Socony) merged in 1931, after the government gave up attempts to prevent it. The newly-combined entity, Socony-Vacuum Corp, was the world's third-largest oil company.
In 1955, the company became Socony Mobil Oil Company. In 1966, it was renamed Mobil Oil Corporation, later shortened to Mobil Corporation. 
Mobil, previously known as the Socony-Vacuum Oil Company, a major American oil company, merged with Exxon in 1999 to form a parent company called ExxonMobil. It was previously one of the Seven Sisters that dominated the global petroleum industry from the mid-1940s until the 1970s. (2)
The 1955 and 1959 Dubuque City Directory listed 300 E. 6th.
1. "Vacuum Oil Company," Wikipedia. Online: https://en.wikipedia.org/wiki/Vacuum_Oil_Company
2. "Socony Mobile Oil Company," Wikipedia. Online: https://en.wikipedia.org/wiki/Mobil