Quote from zdreg:
"Manias, Panics, and Crashes (written in the early 1800s)"
what makes you think this book was not written in the 20th century?
Sorry.. wrong title. I was thinking of:
Extraordinary Popular Delusions and the Madness of Crowds
http://www.amazon.com/Extraordinary-Popular-Delusions-Madness-Crowds/dp/1897597320
First published in 1841