Artist Peter Pietrangeli

On April 19, 1943, Hofmann ingested 0.25 milligrams (250 micrograms) of the substance. Less than one hour later, Hofmann experienced sudden and intense changes in perception. He asked his laboratory assistant to escort him home. As was customary in Basel, they made the journey by bicycle. On the way, Hofmann's condition rapidly deteriorated as he struggled with feelings of anxiety, alternating in his beliefs that the next-door neighbor was a malevolent witch, that he was going insane, and that the LSD had poisoned him. When the house doctor arrived, however, he could detect no physical abnormalities, save for a pair of incredibly dilated pupils. Hofmann was reassured, and soon his terror began to give way to a sense of good fortune and enjoyment, as he later wrote... "... Little by little I could begin to enjoy the unprecedented colors and plays of shapes that persisted behind my closed eyes. 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 ..."