The following is from the book "Ottumwa: Yesterday and Today" published in 1923.
"The Nichols Manufacturing company, 401 to 405 West Main street, with an annual production of 55,000 framing and carpenters' squares, is one of five factories in the United States which makes squares and the only one west of New England according to Fred Hardsocg, owner and manager.
In 1901 four men formed a partnership for manufacture of a framing square on which Moses Nicholls, a carpenter, had secured a patent. The four men were Mr. Nicholls, Martin Hardsocg, T.F. Norfolk, and A. Wheeler. Martin Hardsocg purchased first the share of Mr. Wheeler and later that of Mr. Nicholls, and Fred Hardsocg, his son, purchased the interests of Mr. Norfolk. Later he bought the remainder of the holdings from his father and has been managing the business for about ten years.
The plant is operating at capacity and is unable to meet the demand. In addition to squares the Nicholls Manufacturing company produces floor scrapers, wood pullers, and grass hooks. When the company was established it was a real pioneer in the west and in order to obtain the expert workmanship desired Joseph Miller, and eastern mechanic, was employed to come here. He made the first square and is still with the firm."