April 19 is a historic day in psychedelic culture. Commonly referred to as Bicycle Day, the date celebrates Swiss chemist Albert Hofmann’s discovery of the mind-bending substance called lysergic acid diethylamide — better known as LSD.

Gearing Up for a Ride

Hofmann unknowingly synthesized LSD on November 16, 1938, while researching lysergic acid derivatives in an effort to create a respiratory and circulatory stimulant. It was set aside for five years, until Hofmann decided to take one more look at it.

While re-synthesizing the substance on April 16, 1943, Hofmann accidentally absorbed a small amount through his skin and began to experience minor, but notable, side effects. Looking to document his experiences with the drug, Hofmann decided to experiment with the effects of the substance in his lab in Basel, Switzerland.

Albert Hofmann

Albert Hofmann in 1993. Credit: Philip H. Bailey via Wikimedia (CC BY-SA 2.5).

It was on April 19, 1943, at 4:20 p.m. that Hofmann ingested his first intentional dose of LSD. However, it soon became apparent that he had taken far too much of the hallucinogen and decided that it was best to leave his lab and head back home. Unable to take a car due to wartime restrictions, Hofmann and his lab assistant took bikes instead. Low and behold, the drug’s powerful effects only increased during his bicycle journey that day.

Hofmann’s psychedelic trip became more intense as he arrived home. As the day went on and his experience grew darker, he began to believe he was possessed by a demonic entity. Experiences with his neighbor, who came by periodically to check on Hofmann’s well-being, began to take the form of a nightmare, as faces and voices distorted into dark and twisted psychedelic sounds and images.

The Light at the End of the Tunnel

As the hallucinogenic experience raged on, Hofmann’s doctor came by to check on his vitals, giving him a clear pass with a notation regarding his dilated eyes and sent him off to bed to rest.

Hofmann wrote in 1983, “The horror softened and gave way to a feeling of good fortune and gratitude.” It was at this point in Hofmann’s notes that he was able to enjoy his psychedelic experience as the intensity began to fade and beautiful images, shapes, and colors began to flood his mind behind his closed eyes.

Psychodelic spirals

“Kaleidoscopic, fantastic images surged in on me … circles and spirals, exploding in colored fountains… ” – Albert Hofmann

Riding Into Tradition

The first official Bicycle Day was celebrated 42 years later, in 1985. It was founded by Thomas B. Roberts, a professor of educational psychology at Northern Illinois University, in DeKalb. Roberts chose April 19 to honor Hofmann’s first intentional exposure with LSD, and also because the 16th fell on a Tuesday in 1985 — not ideal for a psychedelic celebration.

LSD as Art

Ripley’s friend, Mark McCloud, first educated us on this unusual holiday while the team was in California documenting his expansive collection. McCloud’s San Francisco home is filled with tens of thousands of LSD tabs known as blotters.

Blotter Art

Blotter art varies from the simple to the elaborate. Courtesy of Mark McCloud – Institute of Illegal Images.

Don’t fret — the acid on McCloud’s tabs have since expired and now serve as a canvas for the intricate art they are covered in. LSD breaks down quickly in the presence of light and heat, and McCloud’s tabs are too old to give anyone ingesting them a trip. Instead, he keeps the tabs as art pieces.

Watch the video to learn more about this unique culture and McCloud’s unbelievable collection.


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