In 1849 Jacobs moved to San Francisco, California traveling aboard ship by way of Cape Horn. He spent about six years, from 1850 to 1856, in California and western Arizona. At Ajo, Arizona he worked as an assayer in the mines near Yuma and Arizona City. He then lived in Victoria, British Columbia, Canada and later made his way to South America, living in Chile, Bolivia, and Peru, where he was engaged in mining also. In 1874 Jacobs married Miss Rosa Mulet, the accomplished French-Chilean daughter of a merchant in Valparaíso, Chile. They moved to Lima, Peru where he began interests in mines and politics and, published a semi-weekly newspaper, El Tumbes, and the Imprenta Americana. For a time he served as the American Vice-consul at Lima, Peru. Four of their eight children were born in Peru: Elizardo Antonio Jacobs, Leyendo, Laura, and Ricardo Benjamin Jacobs . At the outbreak of war between Bolivia and the joint forces of Chile, and Peru in 1879, the War of the Pacific, the Jacobs family returned to Oakland, California and shortly afterward, moved to Tucson, Arizona. After arriving in the "Old Pueblo" in March 1880, he established an assay office and continued in the assay business until he died on May 23, 1899 while visiting Los Angeles, California. Rosa Jacobs was a respected music teacher in Tucson and, later, Oakland and San Francisco. During the time the Jacobs lived in Tucson he owned and operated several mines in the Mexican state of Sonora as well as in Arizona. Some were silver mines. In 1883, Jacobs was one of the parties involved in the famous San Ricardo mine case, which finally was decided by the Arizona Territory Supreme Court in 1886 and reported in Volume II of Arizona Supreme Court case records. The case was over the role of assayers when acting as brokers between mine vendors and mine purchasers. In 1884 in partnership with Tom Childs, Sr., Jacobs re-located the Ajo Mines and established a permanent camp where they began working and mining copper, and processing the ore from the mine. A small ore milling plant was established about 1897 that was operated by Jacobs and his sons. The Ajo mines were sold by Childs and Jacobs to A. J. Shotwell, a promoter, in the fall of 1898. At the time of his death, the vast ore body had yet to be worked. Not until 1912 did a well-financed operation open the large deposit via an open pit copper mine. The holdings were later sold to the Phelps Dodge Corporation, now Freeport McMoRan. Washington Michael Jacobs was duly elected as Justice of the Peace of the Tucson Precinct of Pima County in 1887 and started his term of office on January 1, 1888 for a period of two years. He served as precinct judge during elections in the 1890s, a respected citizen of Tucson. In their youths, his sons worked in the assay shop and chemical laboratory. One, Dr. Benjamin R. Jacobs, became a prominent early biochemist in Washington, D. C. and New York City. Wash Jacob's oldest son, Elizardo, continued in his father's footsteps as Tucson assayer and mining engineer. Elizardo graduated from the mining school at the University of Arizona, where he also worked in the school's assay lab for $45 per month while in school. In 1901 he opened the E. A. Jacobs assay office at Congress and Main, Tucson. He married Bella Amanda Carrillo from a prominent Tucson family. They had ten children. His sons Benjamin, E. A, Jr. and Arthur continued the business on Main and, after the urban renewal/removal of the barrio, at South 10th Avenue. Washington Michael Jacob's descendants kept the assay business going in Tucson until July 2011, when great-grandson Michael Jacobs retired. At 131 years, the Jacobs family assay office tradition was the oldest in the country when it closed.
