First published in 1841, this history chronicles the popular foolishness of Mackay’s day. It is divided into three broad categories, including ‘National Delusions, ‘ ‘Peculiar Follies, ‘ and ‘Philosophical Delusions.’ The author discusses and usually debunks a wide variety of subjects and events. These include economic bubbles like the tulip craze of Holland in 1637 or the Mississippi Company financial bubble of 1719; alchemy, which was of particular interest to individuals who wanted to create gold out of lesser-valued materials; the Crusades, also known as the Middle Ages mania; witch hunts, the persecution of thousands of innocent victims that arose from either supernatural ill fortune or neighbors with a score to settle; duels; the political and religious influence on beards; and several others. This work, with all of its interesting observations, is an entertaining and insightful book that explores the phenomenon of crowd mentality.