Mabel MacFerran Rockwell

Mabel MacFerran was born in Philadelphia, Pennsylvania, in 1902 to Edgar O. and Mabel Alexander MacFerran. Her father was an electrical engineer and her mother an astronomer and mathematician. She was raised in the Quaker tradition. She attended the Germantown Friends School in Germantown, Pennsylvania. In 1925, she graduated with a B.S. in science, teaching, and mathematics (Sigma Xi) first in her class at the Massachusetts Institute of Technology. She received the Elwell Fellowship to attend Stanford University. There she worked with Professor Harris J. Ryan in the million volt laboratory. == Career ==

In 1926, MacFerran joined the Southern California Edison Company Limited as an apprentice testman, becoming the technical assistant to the operating engineer in 1928. In 1932, she became an assistant electrical engineer at the Metropolitan Water District of Southern California at Los Angeles. From 1951 to 1953, she was an electrical engineer with the United States Bureau of Reclamation in Sacramento, California and Fresno, California. She was chief of the power section in the San Joaquin Valley district office in Fresno. She undertook various special assignments and consulting work from 1954 until early 1958. In 1958, she went to work for Westinghouse where she designed the electrical control system for the UGM-27 Polaris missile launcher. Despite her work in the field, by 1949 she was advocating for a turn from weapons development to working for peace. In an interview with the LA Times, she said: "We know enough about the atom—now it's time for intelligent men everywhere to develop spiritual values. Americans must halt their pursuit of more technical knowledge and devote their time to the elimination of war by turning from things of the mind to things of the spirit." == Awards, honors and memberships ==

MacFerran became an associate member of the American Institute of Electrical Engineers (AIEE) in 1928, one of the first ten women to join the professional association. She became an AIEE member in 1935. In 1929 she won the Initial Paper Prize in the AIEE 8th District for her paper "Parallel Operation of Transformers Whose Ratios of Transformation are Unequal." In 1934 she won the AIEE Pacific District prize for "Power Limits of 220 Kv Transmission Lines" with co-author A. A. Kroneberg. == Publications ==

• "Parallel Operation of Transformers Whose Ratios of Transformation are Unequal", 1930 • "Power Limits of 220-Kv Transmission Lines" (with Alex A. Kroneberg), 1934 • "Empirical Method of Calculating Corona Loss From High-Voltage Transmission Lines" (with Joseph S. Carroll), 1937 • "Empirical Method of Calculating Corona Loss From High-Voltage Transmission Lines" (published discussion with E. C. Starr and author), 1938 • "The Development of Aircraft Spotwelding", 1941 • "Mechanics of Deep Drawing Sheet Metal Parts" (with Given Brewer), 1942 • "Stretch-Forming Contoured Sheet Metal Aircraft Parts" (with T. H. Hazlett), 1942 • "Measurements of Drawing Properties of Aluminum Sheet" (with Given A. Brewer), 1942 • "Stress-Strain Relationships in Drawing of Materials" (with G. A. Brewer), 1942 • "Some Factors Affecting the Drawability of Aluminum Sheets" (with G. A. Brewer and V. N. Krivobok), 1942 • "The Effect of Weld Spacing on the Strength of Spot-Welded Joints" (with R. Della-Vedowa), 1942 • "Electrical Power in Aircraft", 1944 ==Legacy==

Mabel MacFerran Rockwell was the first and only woman to design, develop, and oversee the installation of the power generating equipment for the Hoover Dam and the associated transmission equipment to move the power from the Dam to points of use. She was one of the first three women fellows of the AIEE, along with Edith Clarke and Vivien Kellems. == Personal life ==

MacFerran married fellow engineer Edward W. Rockwell on June 7, 1935. Because they were both members of the AIEE, the society's journal Electrical Engineering deemed the event newsworthy and published an account in the July 1935 issue. The Rockwells became the fourth couple where both partners were members of the society. At the time, there were only nine female members of the AIEE. MacFerran and Rockwell divorced in 1958. A memorial service was held at Stanford Memorial Church. == Additional reading ==

Johnson, Vicki (2025). Chapter 10 "Mabel MacFerran Rockwell". In Craig, Cecilia; Teig, Holly; Kimberling, Debra; Williams, Janet; Tietjen, Jill; Johnson, Vicki (eds.). Women Engineering Legends 1952-1976: Society of Women Engineers Achievement Award Recipients. Springer Cham. == External links ==