I've wondered about this for years, ever since I heard that Hard Times was also an industrial novel. These two stories even appeared back-to-back in Dickens ran his story in weekly installments from April to August in his magazine, Household Words.
Gaskell's story ran from September to January of the following year. How are these two works similar? Well, in Dickens' book there is a dirty industrial town, a self-made manufacturer with a mother who worships him!
And there are similar strains in highlighting what is lacking in the industrial society of the day. Dickens' overall theme boils down to a warning that in the intellectual and self-satisfied excitement of lauding science and industry, it is vital to remember that humans are not machines or numbers, but individuals who need nurturing and care.
Focusing on facts, statistics, bank accounts and social esteem deadens us to matters of humanity. It's the lower classes--Cissy Jupe, Stephen Blackpool, and Rachel--who understand what life is really about: love. The most pointed difference, for me, between Hard Times and North and South is in the depth of the characters drawn by the author.
Dickens uses exaggerated characters to make his pointed social commentary. It's difficult to feel an intimate connection with characters that are more symbolic than realistic. I felt the most sympathetic connection with the poor weaver, Stephen Blackpool, whose situation and hope reflects the reality of many hard-worn lives of every century. With Gaskell's characters, I can sympathize with each and every one for their very human faults, habits, and virtues.
