In the Victorian Era, "the language of flowers" (floriography) was all the rage. According to The Smithsonian Gardens History in Bloom summary (and activities sheets) for The Language of Flowers (PDF), "Nearly all Victorian homes would own at least one of the guide books dedicated to the ‘language of flowers.’ The authors of these guidebooks used visual and verbal analogies, religious and literary sources, folkloric connections, and botanical attributes to derive the various associations for the flowers." But where did it come from? (Google books preview) Istanbul in the Tulip Age (PDF, first chapter of Crime and Punishment in Istanbul: 1700-1800), and Turkish love-letters and harems ... somewhat. [more inside]
The History of the Tulip: an educational animated short video for the Tulip Museum in Amsterdam. [via]
Brendan Fitzpatrick took x-ray photographs of flowers that can be magnified by clicking on them.
Men, it has been well said, think in herds; it will be seen that they go mad in herds, while they only recover their senses slowly, and one by one
Extraordinary Popular Delusions And The Madness Of Crowds, Charles McKay's 1841 classic work on mass hysteria and national crazes, still surprisingly readable and engaging. Among the classic examples in McKay's book are the South Sea Bubble, one of the earliest and largest financial bubbles, and the witch hunts of Europe (related: try the 1628 Witch Hunt simulation). Most people remember him best for his history of Tulipmania, the Dutch flower-speculation explosion of 1647 and 1648... except that it may not have been a delusion at all, but rather a rational response to changes in regulation.
This ain't no finger paintin', baby.