In 1839 Frances Trollope decided to write a novel on young factory workers. She had become interested in the subject after reading a copy of the book on the life of Robert Blincoe published by John Doherty in 1832. Before writing the novel she carried out a fact-finding mission to Manchester. Frances Trollope was accompanied by the French artist, Auguste Hervieu, who had been commissioned to produce illustrations for the book. Trollope and Hervieu spent several weeks visiting factories and having meeting with people involved in the campaign for factory reform. This included Richard Oastler, Joseph Raynor Stephens and John Doherty, the editor of The Poor Man's Advocate.

The first part of Michael Armstrong: Factory Boy, was published in 1840. Frances Trollope was the first woman to issue her novels in monthly parts. Costing one shilling a month, it was also the first industrial novel to be published in Britain. The conservative The Athenaeum, gave it a hostile reception and compared Trollope to James Rayner Stephens: "The most probable immediate effect of her pennings and her pencillings will be the burning of factories and the plunder of property of all kinds. The Rev. James Rayner Stephens has recently been sentenced to eighteen months imprisonment for using seditious and inflammatory language. The author of Michael Armstrong deserves as richly to have eighteen months in Chester Gaol. But if the text be bad, still worse are the plates that illustrate it. What, for instance, must be the effect of the first picture in No. V1 (mill children competing with pigs for food), on the heated imaginations of our great manufacturing towns, figuring as they do in every book-seller's window."

The novel tells the story of Sir Matthew Dowling, a wealthy businessman, who adopts Michael Armstrong, a factory child. Dowling uses the boy to illustrate his willingness to help those in need. However, Dowling gets bored with Michael and decides to get rid of him by apprenticing him to an establishment for unwanted pauper children. Michael escapes and after many dangerous adventures is reunited with the factory girl who he loved as a child. The main message of the novel is that individual philanthropy is an inadequate solution to the problems of industrialisation.

Several of the passages in Michael Armstrong: Factory Boy are based on events described in Robert Blincoe's Memoir. Some of the novel's critics pointed out that this was a book about conditions in the early days of the century. Frances Trollope was also attacked for producing a book that could be purchased in parts and therefore available to the working class. One critic suggested that books like this should be left to male writers as "women are more at home in the flower garden and by the domestic hearth."