Her father, Robert James Allman Barnard, became a foundation professor of mathematics at the Royal Military College, Duntroon near Canberra, where the family moved in 1911.
[1][5] Her master's thesis concerned the continuum mechanics of a cracked thin plate, and was supervised by John Henry Michell.
[5] In search of a subject that would bring her into more contact with other people, and discouraged by the job prospects for mathematicians and physicists in Australia, Barnard shifted her interests to biometrics.
[1][5] After completing her education, Barnard returned to Australia and became an assistant biometrician in the Division of Forest Products of the Council for Scientific and Industrial Research, beginning in 1936.
[6] In the normal course of events, she would have lost the position when she married in 1939,[5][2] but the outbreak of World War II, and the need for wood in airplanes, caused greater demands on her office, so her resignation was delayed until the birth of her first child in 1941.