Features and Occasionals

Bicycle Day

By Trisha McMillan

Twas the 19th of April, 1943 in Basel, Switzerland, and Sandoz Labs chemical researcher Albert Hofmann had been researching a derivative of ergot fungus, attempting to isolate a new anti-hemorrhaging drug. Three days before, on Friday, April 16, Hofmann had noticed some odd dizziness and restlessness after he’d been working with the new extract, and so in the course of seeking more information on the next working day he deliberately exposed himself to what he thought was a safely minuscule dose: a quarter milligram.

The threshold dose for the new drug, Lysergic acid diethylamide, or LSD-25, is actually 20 micrograms…so starting about 40 minutes later, Dr. Hofmann began the first ever acid trip.

Startled by the sudden intense changes in his perception, he asked a laboratory assistant to accompany him home. As this was during the Second World War and cars were prohibited on the roads, the two scientists embarked upon the journey by bicycle.

Hofmann’s experience expanded during the ride, and by the time he arrived home he was struggling with paranoia and anxiety. His doctor was summoned to examine him, but could find nothing physically wrong with Hofmann except his hugely dilated pupils. Thus reassured, Hofmann’s terror waned and he began to enjoy his experience.

“Kaleidoscopic, fantastic images surged in on me, alternating, variegated, opening and then closing themselves in circles and spirals, exploding in colored fountains, rearranging and hybridizing themselves in constant flux. It was particularly remarkable how every acoustic perception, such as the sound of a door handle or a passing automobile, became transformed into optical perceptions. Every sound generated a vividly changing image, with its own consistent form and color,” he later described.Unwittingly, Hofmann had set the stage for the psychedelic revolution of the late 1960s.

In 1985, educational psychology professor Thomas B. Roberts at Northern Illinois University founded the first Bicycle Day celebration at his home. “I originally wanted to celebrate the 16th, but that year the 16th was midweek and not a good day for a party, and the 19th was on a weekend, so I decided to celebrate the first intentional LSD exposure instead of the first exposure on the 16th. Had the calendar been different, the 16th would have been Bicycle Day.” Roberts’ work specializes in psychedelics, particularly in their entheogenic or spiritual uses.

At one point Dr. Hofmann asked Roberts why he had called it Bicycle Day instead of LSD Day.

“I told him that the bicycle was a more concrete image than a chemical structure, and in America there is a famous poem that marks the start of our revolution in 1775 that makes a parallel with his ride. It begins:

‘Twas the eighteenth of April in ’75
And hardly a man is now alive
Who remembers that famous day and year
And the midnight ride of Paul Revere.
American school children used to memorize this poem. The Hofmann ride and the Revere ride are analogous, each marking the beginning of a new era

For a free online copy of Albert Hofmann’s book, LSD: My Problem Child, go here:

Available in May 2013:
LSD and the Divine Scientist: The Final Thoughts and Reflections of Albert Hofmann; foreword by Christian Ratsch (Bear & Company)

Available in June 2013:
Mystic Chemist: The Life of Albert Hofmann and His Discovery of LSD, by Dieter Hagenbach and Lucius Werthmüller; foreword by Stanislav Grof (Synergetic Press)

This article was originally published on March 29, 2013.