Encyclopedia Dubuque
"Encyclopedia Dubuque is the online authority for all things Dubuque, written by the people who know the city best.”
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Affiliated with the Local History Network of the State Historical Society of Iowa, and the Iowa Museum Association.
SINCLAIR OIL COMPANY
SINCLAIR OIL COMPANY. Harry F. Sinclair at the age of twenty lost nearly everything he owned in a bad speculation – including the drug store his father had left him. He became interested in the oil business and starting small by selling lumber to oil derricks while buying and selling leases on the side. He was able to locate productive oil sites, and soon he was picking up support from wealthy investors.
By age 31, Sinclair was the richest man in Kansas. In 1916, at age 40, he officially formed Sinclair Oil Corporation out of the assets of eleven small petroleum companies, and by the late 1920s, it was the seventh largest oil company in the United States.
Dinosaurs first appeared in Sinclair marketing in 1930 as part of a campaign to educate customers on the origin of fossil fuels. The Apatosaurus (then thought a brontosaurus) quickly surpassed the T-Rex and triceratops in popularity. By 1932, Sinclair had registered Dino as a trademark. In 1976 Mr. and Mrs. Earl Holding purchased Sinclair Oil from Pasco. As a privately-held, family-owned company, Sinclair in 2018 was one of the oldest continuous brands in the oil business.
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Source:
Sinclair Oil Company. Online: https://www.sinclairoil.com/history/
The 1948 Dubuque Classified Business Directory listed 2490 University.
The 1957 Dubuque City Directory listed 408 W. Locust.