54. The Sun as a Chemist

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Stories About Chemistry

54. The Sun as a Chemist

Once Stephenson, the inventor of the steam locomotive, was taking a walk with his friend Beckland, a geologist, near the first railway in England. Presently they saw a train passing.

    "I say, Beckland," asked Stephenson, "what do you think makes that train go?"
    "Why, the hand of the driver of one of your wonderful locomotives."
    "No."
    "Well then, the steam that moves the machine?"
    "No."
    "The fire kindled under the boiler?"
   "Wrong again; it is actuated by the Sun which shone in that far-off epoch when the plants were alive that afterwards changed into the coal which the driver is shovelling into the stoker."

All living things owe their origin to the Sun, especially plants. Try and grow them in the dark, and all you will get is pale thin filaments instead of juicy green stalks. Under the action of solar light chlorophyll (the colouring matter of green leaves) converts the carbon dioxide of the air into complex molecules of organic substances which constitute the bulk of the plant.

Hence, the Sun, or rather its rays, are the chief "chemist" synthesizing all the organic substances in plant? It would seem so. Not in vain has the process of assimilation of carbon dioxide by plants been named photosynthesis.

It is known that many chemical reactions occur under the action of light. There is even a special branch of chemistry which studies them, called photochemistry.