I think it would be a great sign to put in the window of a small business : GONE BERSERK . Maybe with one of those cardboard clocks indicating a return time . I was talking to my Danish friend Ivan yesterday . I mentioned Ivan in a recent post —– the guy who bad-mouths the Irish , most likely , in my opinion , because his Viking ancestor sailed his longboat back to Scandinavia rather than stay in Ireland as some of the other guys did . Missed his chance . Sour grapes , Ivan . Anyway. Ivan wants me to check out an antiquarian book convention in Pasadena for him . ” You might find some images of those chimneys ,” he suggested . ” What was it you were interested in ?” ” Backyard incinerators . ” ” You’d be surprised what these guys might have,” he said . Ivan is a book dealer . ” I’d like to find images of Amanita mushrooms . The ones the Vikings used before they went on their crazy raids . “ I’d never heard of Amanita mushrooms , a poisonous little white toadstool with red spots . ” That’s how Santa Claus got his hat , ” he said . Ivan speaks with authority . I’ve since read some theories about how those reindeer could work themselves up enough to fly that sleigh all over the earth ………… Turns out there were Norse warriors who fought in an almost uncontrollable frenzy while wearing wolf pelts . They’re called Berserkers . Some people have speculated throughout history that the frenzied , trance-like state , was a result of ingesting the Amanita mushroom as a hallucinogenic . The Anglo-Saxons across the sea in Britain , busy collecting the extortion money , the Danegeld , to buy off the Viking raiders , described the craziness as ” gone berserk ” . The Berserkers are mentioned in old Norse sagas . They were sometimes referred to as Odin’s Warriors . But , it is unclear just how they worked themselves into their frenzied rage . The hallucinogenic mushroom theory didn’t , apparently , come around until a Swedish professor , Sam Odmann , proposed it in 1784. Yeah , Odmann . But , given the historical rivalry between the Swedes and the Danes , I don’t have much confidence in this theory , despite my friend Ivan’s certainty . Could it have been, rather , a result of a religious-type trance ? Maybe it was a consequence of too much Tuborg ? Too many bottles of Carlsberg ? O.K. , maybe I got my centuries mixed up . I may look for images of Ivan’s favorite mushroom when I go to the book event . I’ll ask the dealers for “death caps” or “destroying angels” and see what happens . One of those antiquarians may know about Amanita muscaria , which was powdered and mixed with milk and used as an insecticide . All exciting stuff . To someone . To Vikings .