Date: 1787

"They will not always expertly distinguish the several species of geniuses, the golden, the silver, the brazen, and the iron."

— Adams, John (1735-1826)

Date: 1845

"No words, no tears, no prayers, from his gory victim, seemed to move his iron heart from its bloody purpose."

— Douglass, Frederick (1818-1895)

Date: 1845

"Under its influence, the tender heart became stone, and the lamblike disposition gave way to one of tiger-like fierceness."

— Douglass, Frederick (1818-1895)

Date: 1845

"I then presented an appearance enough to affect any but a heart of iron."

— Douglass, Frederick (1818-1895)

Date: 1854

"They love the soil which makes their graves, but have no sympathy with the spirit which may still animate their clay."

— Henry David Thoreau (1817-1862)

Date: 1922

"When the two gases previously mentioned are mixed in the presence of a filament of platinum, they form sulphurous acid. This combination takes place only if the platinum is present; nevertheless the newly formed acid contains no trace of platinum, and the platinum itself is apparently unaffected...

— Eliot, T. S. (1888-1965)

Date: February 8, 1996

"These laws would declare ideas to be another industrial product, no more noble than pig iron."

— Barlow, John Perry (b. 1947)

Date: 2001

"Pebble, question, soul: no one can see all sides at once, but there is no side that cannot be seen."

— Richardson, James (b. 1950)

Date: October 28, 2012

"Each grasped, in the unflinching gaze of the other, a silent acknowledgment of the nobility of man, especially as manifested in work, the work that purified the soul the way steel is purified in the smelter. That sort of thing."

— Saunders, George (b. 1958)

Date: June 19, 2013

"Where they (it was held) re-made the world visually and emotionally in the smithies of their tortured souls (to paraphrase James Joyce), Warhol blithely swiped subject matter from mass media."

— Sartwell, Crispin (b. 1958)