Thomson was principal of Queen's College, Ballarat for some time. In 1881, she opened a boarding and day school for girls in Spring Street, Melbourne.[1]
Thomson began writing investigative articles, being referred to in The Bulletin in 1886 as "the female 'Vagabond' of Melbourne".[2][3] Thomson worked as an undercover journalist, disguising herself as a man to visit brothels and taverns investigating corruption which was exposed in her newspaper articles.[2] She investigated undercover as an attendant at the Kew Asylum, a psychiatric hospital in Melbourne[1] and also as an assistant nurse at the Melbourne Hospital.[4]
Thomson was one of the founders of the Austral Salon in 1890,[1] a women’s club to foster literature, music and the arts.[2] In 1899, Thomson and Evelyn Gough became joint proprietors of The Sun: An Australian Journal for the Home and Society.[5][6][7] After the magazine merged with Arena in 1903 Thomson became a literary agent.[8]
Thomson married Thomas Floyd Legge in Melbourne in 1918, aged 72.[1] The wedding was held at the Women Writer’s Club.[1] Thomson died in Cheltenham on 24 July 1928.[10]