John F. Slater (1815-1884) was a wealthy mill-owner who resided in Norwich. As related in the Memorial of John F. Slater, of Norwich, Connecticut, 1815-1884 (1885):
On the death of John Slater, May 27, 1843, his sons John F. and William S. inherited his interest in the mills at Hopeville and Jewett City, Conn., and at Slatersville, R. I., and they formed a partnership under the name of J. & W. Slater, adjusting their affairs so as to be equal partners. In March, 1845, this firm sold their Hopeville property, and in 1849 bought the interest of Samuel Slater’s heirs in the mill at Slatersville. In 1853, after the lease of this last-mentioned property to A. D. and M. B. Lockwood had expired, William S. Slater took the management of the Slatersville mill, and John F. Slater that of the Jewett City mill. The partnership of the brothers continued until Jan. 1, 1873, when it was dissolved, each taking the mill of which he had been the manager.
John F. Slater was also a principle investor in what would become the Ponemah Mills in Taftville. According to the “Walking Guide to Historic Broadway & Union Street,” the house at 274 Broadway in Norwich was built c. 1870 and in the late nineteenth century was the home of his son, William A. Slater (1857-1919). The book Norwich in the Gilded Age: The Rose City’s Millionaires’ Triangle (2014) by Patricia F. Staley, explains that the house at 274 Broadway was the home (by 1876) of Marianna Lanman Hubbard Slater (1824-1889), who married John F. Slater in 1844. (presumably she lived in the house with her husband). That book indicates that her son, William A. Slater, lived [at some point] in the Slater mansion, a now demolished house at 228 Broadway. William Slater founded the Slater Memorial Museum in Norwich in honor of his father. In the 1950s, the house at 274 Broadway became the residence of the Roman Catholic Bishop of the Diocese of Norwich.