Albert Hofmann

I suddenly became strangely inebriated. The external world
became changed as in a dream. Objects appeared to gain in relief;
they assumed unusual dimensions; and colors became more glowing.
Even self-perception and the sense of time were changed. When the
eyes were closed, colored pictures flashed past in a quickly changing
kaleidoscope. After a few hours, the not unpleasant inebriation,
which had been experienced whilst I was fully conscious, disappeared.
what had caused this condition?

Albert Hofmann - Laboratory Notes (1943)

Dr. Albert Hofmann worked for Sandoz Chemicals in Basel, Switzerland in the 1930's and 1940's. In 1938 he was exploring the medical uses of ergot alkaloid derivatives (from ergot fungus that infects grain). He had synthesised 25 different Lysergic Acid compounds in the search for an effective circulatory and respiratory stimulant (an analeptic) but no benefits were identified during animal tests other than to make the animals "restless".

However, in April 1943 Hofmann, based on a "peculiar presentiment" he experienced, he decided to synthesise another batch of LSD-25. As he recorded in his laboratory report:
Last Friday, April 16,1943, I was forced to interrupt my work in the laboratory in the middle of the afternoon and proceed home, being affected by a remarkable restlessness, combined with a slight dizziness. At home I lay down and sank into a not unpleasant intoxicated-like condition, characterized by an extremely stimulated imagination. In a dreamlike state, with eyes closed (I found the daylight to be unpleasantly glaring), I perceived an uninterrupted stream of fantastic pictures, extraordinary shapes with intense, kaleidoscopic play of colors. After some two hours this condition faded away.
Attributing the experience to absorbing a tiny amount of the LSD-25 that he had synthesised, he decided to take a larger dose three days later.

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