Source: U.S. Department Of Commerce, Record Book, Part Ii, P. 18.
This NBER data series m01192 appears on the NBER website in Chapter 1 at http://www.nber.org/databases/macrohistory/contents/chapter01.html.
NBER Indicator: m01192
Release: NBER Macrohistory Database
National Bureau of Economic Research, Pig Iron Production, Merchant's Furnaces for United States [M01192USM576NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M01192USM576NNBR/, July 5, 2015.