Exxon had adroitly maneuvered during the 1910s to acquire the Barrancabermeja field, and Gulf Oil Co, (owned by Andrew Mellon) did the same to acquire the Barco Concession near Cúcuta (Map 1). These two fields contained the main oil deposits in Colombia, and many members of the Colombian elite expected these acquisitions to produce great rivers of wealth for their country. These hopes were dashed during the first half of the 1920s: Exxon in Barrancabermeja considered the export of crude to be its main concern, and other issues, such as local supply of gasoline, were secondary; Gulf did not even bother to exploit the Barco Concession but merely kept it as a reserve. Exxon was supposed to pay the Colombian government a mere 10 percent crude royalty for extracting the oil that naturally oozed to the surface, and in fact it normally paid even less by recourse to numerous subterfuges. By the mid 1920s, Colombia, rather than swimming in wealth, was instead drained by the practices of the U.S. oil companies. 1 A faction within the Colombian elite felt that this situation was unacceptable, and during the presidency of Miguel Abadía Méndez (1926-1930), Minister of Development José Antonio Montalvo led the dissatisfied elements in a campaign to reverse Colombia's petroleum policy and rescue the Barco Concession.