The answer is fairly simple: they weren't. There was little or no legislation anywhere in the nation protecting workers until 1874 when Massachusetts passed a law limiting the hours women and children could work in factories to ten hours per day. Although the Industrial Revolution can be traced back as far as 1793 when Eli Whitney invented the cotton gin, and despite the rapid growth of factories and cities in the United States, mostly in the North, American workers were important but forgotten cogs in the machinery of the new economy. Working conditions in American factories were abhorrent; the fact that a new law limited one's work day to 10 hours a day is indicative of how long the hours normally were. Accidents were frequent, and often deadly. Workman's compensation and insurance were non-existent. As the Northern economy shifted from an agricultural to an industrial one, there were plenty of people who were available to fill factory jobs, and employers were free to hire and fire at will. Some of the earliest anti-immigrant sentiment can be traced to the competition for employment in Northern factories, and Southerners defending the "peculiar institution" of slavery in the years leading up the War Between the States frequently cited the horrible working conditions of Northern factories as being a kind of slavery as well. It wasn't until 1911 when nearly 150 workers perished in the Triangle Shirtwaist Factory fire in New York City that anyone began to suggest that perhaps workers deserved to have some basic rights, including safety, on the job. Even then, protecting workers remained the function of state and local governments until the 1930's.