The Amoskeag Mill was built in 1810,the same year that Manchester received its name (the town had been called Derryfield before that). The mill was located along the Merrimack River,near the Amoskeag Bridge. The mill grew to be the largest cotton mill in the world.
My third great-granduncle, Alexandre Metevier (1852-1930), worked at the Amoskeag Mill during the 19th century, according to a census record from the time.
You can learn more about the Amoskeag Mill here: Amoskeag Manufacturing Company
The following video also provides information about the mill. While it is a low-quality video, it is definitely worth watching.