Five years later Slater and others built a second mill, and in 1806, after Slater had brought out his brother to share his prosperity, he built another.

Workmen came to work for him solely to learn his machines, and then left him to set up for themselves.

The knowledge he had brought soon became widespread.

Mills were built not only in New England but in other States.

In 1809 there were sixty-two spinning mills in operation in the country, with thirty-one thousand spindles; twenty-five more mills were building or projected, and the industry was firmly established in the United States.
The yarn was sold to housewives for domestic use or else to professional weavers who made cloth for sale.