During the 19th century, chemists struggled with discovering how identical carbon atoms combined to form different compounds. This mystery was solved in a most wondrous manner by a chemist named Friedrich August Kekule (1829-1896).
Kekule was returning home late one night after discussing chemistry with his friend, Hugo Muller. While riding home on an open bus through the deserted streets of London, he said:
I fell into a reverie, and lo, the atoms were gamboling before my eyes. . . . I saw how, frequently, two smaller atoms united to form a pair; how a larger one embraced the two smaller ones; how still larger ones kept hold of three or even four of the smaller; whilst the whole kept whirling in a giddy dance. I saw how the larger ones formed a chain, dragging the smaller ones after them but only at the ends of the chain.
Kekule spent much of that night drawing the shapes he saw in his dream. His sketches illustrated how carbon atoms create different substances by forming links and chains. This vision led to Kekule’s theory of organic molecular structure.
Sometime after this discovery Kekule dedicated himself to studying aromatic benzene, a hydrocarbon found in aromatic substances such as scented oils and spices. Benzene does not follow the same rules of organic molecular structuring that Kekule had discovered in his first dream. After laboring for seven years to unlock the secrets of the structure of benzene that accounted for different aromatic properties, Kekule had another revelatory dream. He recalled:
I was sitting writing at my textbook but the work did not progress; my thoughts were elsewhere. I turned my chair to the fire and dozed. Again the atoms were gamboling before my eyes. This time the smaller groups kept modestly in the background. My mental eye, rendered more acute by repeated visions of the kind, could now distinguish larger structures of manifold conformation: long rows, sometimes more closely fitted together all twining and twisting in snake-like motion. But look! What was that? One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes. As if by a flash of lightning I awoke; and this time also I spent the rest of the night in working out the consequences of the hypothesis.
This dream led to Kekule’s discovery that carbon atoms also form rings.
Kekule’s dreams of carbon atoms forming chains and rings answered the question of how identical carbon-based compounds produce different substances. This discovery spawned an organic chemistry industry which today provides indispensable coal-tar products such as dyes, plastics, detergents, and drugs. His dreams also unlocked mysteries of life on earth, for all organic life depends on the capacity of carbon atoms to form molecular chains and rings as they did in Kekule’s dreams.
(Source: Truth and Science: An LDS Perspective)