Metal automobile license tags issued in Worden in 1920 (left) and 1930 (right). MCHS objects 1988-127-0001 and 1993-020-0001, respectively.
Automobile sales in America took off in the post-war years. From 1916 to 1920, the number of cars on the road tripled to 9 million. The price of oil increased 150% to $3.50 per barrel crude.
United States Patent 1,392,629 for Process of Converting Hydrocarbons filed by C.P. Dubbs March 19, 1919, patented October 4, 1921. Source: United States Patent and Trademark Office. View the full patent.
Increased demand for gasoline led to innovations in “cracking.” Cracking used pressurization to break apart fuel oil and kerosene molecules, increasing gasoline yield. C.P. Dubbs patented his “clean circulation” cracking process in 1921. The Roxana Petroleum refinery was an early adopter and began constructing a Dubbs unit in March of 1920. By late 1922, the refinery had worked out the kinks. Construction of six more Dubbs units soon followed.
Over the course of the decade, mass production made automobiles more affordable. More and more Americans purchased them: over 23 million passenger cars traveled the nation’s new paved roads in 1929. Roxana Petroleum changed its name to Shell Petroleum to identify itself more closely in consumers’ minds with the Shell brand on its products.
The refinery’s crude processing capacity reached 35,000 barrels per day.