A timeline. In 1712, Thomas Newcomen invents the first steam engine. In 1973, Eli Whitney invents the cotton gin. In 1837, Samuel Morse invents the American telegraph. In 1877, Thomas Edison invents the phonograph.
In The Red Badge of Courage, when Henry wakes up in camp the day after fighting, he first think he is in a Charnel place because the sleeping men around him look dead.