Bicycle Day is April 19 because on this day in 1943, Dr. Albert Hoffman, a Swiss chemist, working on behalf of Sandoz Pharmaceuticals, first known for Saccharine, dosed himself with 250 micrograms of Lysergic Acid Diethylamide-25, now known as LSD, and then rode his bike home from the lab.
Thus the first acid trip was on a bicycle.
Another example of what was first done with a bicycle is taken by the world and the bike is forgotten.
Whether it’s tensioned spoke wheels, pneumatic tires, gears, paved roads, pro sports, assembly lines, or many other examples, the bike innovates and then is forgotten.
Hoffman must have been a cyclist, because he chose to ride home. A historian noted, “He soon felt so disoriented that he rode his bicycle home.”
As for the top image, it’s in the public domain, having first appeared in an illustrated guide to the Sydney, Australia, Taronga Zoo, sometime in the 1940s. Again, there are bikes, but what people are coming for are the monkeys.