Cook's first volume of poetry, Lays of a Wild Harp, appeared in 1835, when she was only seventeen. Encouraged by its favourable reception, she began to send verses anonymously to the Weekly Dispatch, the Metropolitan Magazine, the New Monthly Magazine, and The Literary Gazette;[3] William Jerdan praised her work in the last of these. After a time she confined herself to the radical Weekly Dispatch, where her first contribution had appeared under the signature 'C.' on 27 Nov 1836,[3] and she became a staple of its pages for the next ten years. Its editor was William Johnson Fox and its owner was James Harmer, a London alderman.[4] She lived for a time at Harmer's residence, Ingress Abbey, in Greenhithe, Kent,[5] and wrote certain of her works there.[6]
Cook's poem The Old Armchair (1838) made hers a household name for a generation, both in England and the United States. In that year, she also published Melaia and other Poems.[2]
Her work for the Dispatch and New Monthly was pirated by George Julian Harney, the Chartist, for the Northern Star. Familiar with the London Chartist movement in its various sects, she followed many of the older radicals in disagreeing with the O'Brienites and O'Connorites in their disregard for the repeal of the Corn Laws. She also preferred the older Radicals' path of Friendly Societies and self-education.
From 1849 to 1854 Cook wrote, edited, and published Eliza Cook's Journal, a weekly periodical she described as one of "utility and amusement." The periodical was described as having "variety, piquancy, benevolent aim, and hardly had a superior" in comparison to other periodicals of the time. Although some found solace in Cook's work, the periodical was short lived due to lack of appreciation among the majority. After a struggle to keep the periodical afloat and through health issues the periodical ultimately fell.[7]
Cook went on to publish Jottings from my Journal (1860), where a lot of Eliza Cook's Journal's contents reappeared. This publication was one of the few times Cook wrote in prose. It included many essays and sketches that were written in a clear and simple manner, usually conveying a moral lesson for the reader. Some of the essays are "mild satires on the social failings of her contemporaries."
She also published New Echoes and Other Poems (1864) which did not find as much success as her previous efforts.[8] Despite a lack of interest in her later works, Eliza Cook was a staple of anthologies throughout the nineteenth century.
