'Women have won their political independence. Now is the time for them to achieve their economic freedom too.'

This was the great rallying cry of the pioneers who, in 1919, created the Women's Engineering Society. Spearheaded by Katharine and Rachel Parsons, a powerful mother and daughter duo, and Caroline Haslett, whose mission was to liberate women from domestic drudgery, it was the world's first professional organisation dedicated to the campaign for women's rights.

Magnificent Women and their Revolutionary Machines tells the stories of the women at the heart of this group - from their success in fanning the flames of a social revolution to their significant achievements in engineering and technology. It centres on the parallel but contrasting lives of the two main protagonists, Rachel Parsons and Caroline Haslett - one born to privilege and riches whose life ended in dramatic tragedy; the other who rose from humble roots to become the leading professional woman of her age and mistress of the thrilling new power of the twentieth century: electricity.

In this fascinating book, acclaimed biographer Henrietta Heald also illuminates the era in which the society was founded. From the moment when women in Britain were allowed to vote for the first time, and to stand for Parliament, she charts the changing attitudes to women's rights both in society and in the workplace.