One more bit from Age of Edison:
In Maine, for example, children continued to work at all hours in sardine canneries during the harvest season. They were roused from their beds whenever the boats arrived after dark ,and worked through the night cutting fish. An investigator reported that “the cannery whistle, not the sun, brings day to the Maine coast.”
As new machines and the longer workday intensified production, children also did night work in bottle and box factories, in coal miens, and in textile mills. The ramshackle villages around southern mills served as a visible reminder that for these workers the new technology offered no comfort or convenience, but was a tool of economic production that only intensified their exploitation.