They then vowed to stop it happening.

Documents from the National Archives of Australia reveal the contempt for women held by the hierarchy of the early public service and how far female public servants have had to travel to achieve workplace equality.

The Royal Commission into Public Service Administration in 1920 found women were "physiologically" inferior to men in the workplace and "usually" had nervous breakdowns if given positions of responsibility.

Royal commissioner Duncan Clark McLachlan decided women could be most usefully employed in "routine" tasks in departmental records branches, at lower wages than men, so that "promising [male] youths" could be released to undertake more meaningful work.

In McLachlan's time, there just were 2645 women working in the 24,000-strong Australian Public Service (there are now more than 90,000) and they were mostly barred from the well-paid Clerical Division, instead employed in lower-status roles such as telephonist, typist or postal assistant.

There were no women in the elite Professional Division and the royal commissioner, a former public service commissioner, wanted it kept that way.

"As regards appointment to the position of clerk, the unrestricted admission of women to these positions would certainly mean the complete transformation of a service now comprised predominantly of men," Mr McLachlan wrote.

"If the future efficiency of the service be kept in view, such a change would be a serious disadvantage."

Mr McLachlan was cool on the idea of women being allowed to occupy large numbers of positions in the mainstream "Clerical Division" of the public service, concluding they were just not up to it.

"It is found they reach their limit of usefulness at a comparatively early age if placed in positions ordinarily filled by men," the royal commissioner wrote.

"While they may stand the strain and pressure of work for a time, usually reaction follows with the accompanying nervous breakdown, and, as a general rule, it is shown that women are physiologically unfitted to carry responsibility at an age when men are improving and developing their capacity in this respect."

Mr McLachlan conceded that demands for female equality were growing in the world beyond the public service, but he felt no need to recommend wage parity for men and women in the bureaucracy.

"The cry of 'equal pay for equal work', irrespective of sex, has been an insistent one," Mr McLachlan conceded.

"Where similar duties are performed by men and women ... the experience throughout the world has been that equal services are not rendered owing to the fact that constitutionally women are unable to give such continuous effort as men and are absent from duty for health reasons to a far greater extent."

Far better for a "contented service", the commissioner concluded, that a small number of routine and repetitive clerical positions be opened to women, at lower rates of pay than their most junior male colleagues.

"This proposal ... would release promising youths from duties which are mainly routine, thus widening their scope for training and their prospects of advancement, while at the same time making for a more contented service," Mr McLachlan wrote.