The atmosphere of this story is depressing. Dr. Heidegger invites 4 friends into his study for an experiment. They are old and unhappy:
They were all melancholy old creatures, who had been unfortunate in life...
Not only are the friends old and dried up, but Dr. Heidegger's study is old and dusty as well, adding to the dark atmosphere:
It was a dim, old-fashioned chamber, festooned with cobwebs and besprinkled with antique dust.
The doctor is experimenting with water from the Fountain of Youth. He asks his friends to help him test the water, which they do, and they return to their youthful selves for a very brief time. Even though the doctor warns them not to make the same mistakes, try to use their new-found youth to help others, they are all selfish, and when they realize their youth only lasts for a few moments, they desperately plan to search further for the Fountain of Youth so they can get more of the elixir. Their bodies are not the only things dried up, but their souls are dried up, because they are selfish and can only think of themselves.
The short story is a comment on human nature, but the mood and atmosphere are very negative in my view.
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