Scientific American Public Domain Materials, Oldest US science mag (est. 1845). Features contributions from Einstein & Nobel laureates. Public domain only (fansite)

David Ricardo, On The Principles of Political Economy, and Taxation

P. T. Barnum, The Art of Money Getting; Or, Golden Rules for Making Money

Robert Henry Thurston, Robert Henry Thurston was an American engineer, and Professor of Mechanical Engineering

Charles Mackay, Mackay engaged in journalism in London: in 1834 he was an occasional contributor to The Sun.