Dr. Heidegger performs a demonstration with the rose for his four guests in order to convince them of the power of the water he has obtained from the Fountain of Youth. He opens a heavy book "which common report affirmed to be a book of magic."

Undoing the silver clasps, he opened the volume, and took from among the black-letter pages a rose, or what was once a rose, though now the green leaves and crimson petals had assumed one brownish hue, and the ancient flower seemed ready to crumble to dust in the doctor's hands.

It used to be a common custom to press flowers between the pages of books, and people today will sometimes be surprised to find a pressed and faded flower in an old book, put there for some sentimental or romantic reason many years ago. Using the rose for a demonstration of the magical powers of the water from the Fountain of Youth is an example of Hawthorne's genius as a creative writer. Every reader in his day would have been quite familiar with the appearance of such withered and forgotten flowers among the pages of books. They always create a brief sensation of sadness and sympathy.

Dr. Heidigger explains that the rose was given to him fifty-five years ago by a girl named Sylvia Ward whom he expected to marry. He does not explain why the marriage did not come off, but he probably assumes that his four aged guests are familiar with his history. He seems like a lonely man who never married and has devoted his life to solitary scientific research.

He throws the dried-up flower into a vase containing the magical water.

The crushed and dried petals stirred, and assumed a deepening tinge of crimson, as if the flower were reviving from a deathlike slumber; the slender stalk and twigs of foliage became green; and there was the rose of half a century, looking as fresh as when Sylvia Ward had first given it to her lover.

Dr. Heidegger gives his guests this demonstration before inviting them to drink the magical water themselves. It is a very effective way of enhancing the verisimilitude of the strange story. Hawthorne was an extremely conscientious writer, and one of his outstanding characteristics was his ability to create the minute details of a setting which make a story seem convincing. For example, in his description of the transformation of the rose he writes:

It was scarcely full blown; for some of its delicate red leaves curled modestly around its moist bosom, within which two or three dewdrops were sparkling.

Hawthorne is simply describing such a lovely, fresh flower as every reader has seen at one time or another but asserting that it is the faded rose magically rejuvenated after fifty-five years. When the four guests drink the water from the Fountain of Youth, their transformations into their younger selves will be all the more credible to the reader. Hawthorne is telling a fantastic tale but beguiling the reader into believing it. He knows the reader will suspend disbelief because he wants to believe in it.