Selos que quase instantaneamente entregam cartas ou pacotes para qualquer destino

Você indicou em um comentário que você pode estar confundindo duas histórias diferentes. Partes da sua descrição correspondem ao conto "Pós-pago ao Paraíso" (também conhecido como "The Stamps of El Dorado") por Robert Arthur , o primeiro de sua série de histórias de Murchison Morks . Publicado pela primeira vez em Argosy , em 15 de junho de 1940, foi reimpresso em A Revista de Fantasia e Ficção Científica , Winter-Spring, 1950 , disponível no Arquivo da Internet . Se você a ler há cerca de 40 anos, pode ter sido em esta antologia de Damon Knight ou em esta antologia de Asimov-Greenberg . Aqui estão alguns detalhes da história para ajudá-lo a lembrar se este é um que você leu antes.

Não há comunicação com pessoas mortas em "Pós-pago para o Paraíso". Não era um menino ou uma menina, mas um homem adulto. . .

It was Hobby Week at the Club, and Malcolm was displaying his stamp collection.

"Now take these triangulars," he said. "Their value is not definitely known, since they've never been sold as a unit. But they make up the rarest and most interesting complete set known to philatelists. They—"

"I once had a set of stamps that was even rarer and more interesting," Murchison Morks interrupted. Morks is a small, wispy man who usually sits by the fireplace and smokes his pipe, silently contemplating the coals. I do not believe he particularly cares for Malcolm, who is our only millionaire and likes what he owns to be better than what anybody else owns.

. . que herdou os selos de seu pai:

I am not a stamp collector myself [he began, with a pleasant nod toward Malcolm] but my father was. He died some years ago, and among other things he left me his collection.

Aqui está uma descrição dos selos (que eram um pouco maiores que os selos regulares):

It is true the subjects they depicted were far from usual. The ten-cent value, for instance, depicted a unicorn standing erect, head up, spiral horn pointing skyward, mane flowing, the very breathing image of life.

It was almost impossible to look at it without knowing that the artist had worked with a real unicorn for a model. Except, of course, that there aren't any unicorns any more.

The fifty-center showed Neptune, trident held aloft, riding a pair of harnessed dolphins through a foaming surf. It was just as real as the first.

The one-dollar value depicted Pan playing on his pipes, with a Greek temple in the background, and three fauns dancing on the grass. Looking at it, I could almost hear the music he was making.

Morks é especialmente fascinado pelo selo de três dólares:

A native girl, against a background of tropical flowers, a girl of about sixteen, I should say, just blossomed into womanhood, smiling a little secret smile that managed to combine the utter innocence of girlhood with all the inherited wisdom of a woman.

Or am I making myself clear? Not very? Well, no matter. Let it go at that. I'll only add that on her head, native fashion, she was carrying a great flat platter piled high with fruit of every kind you can imagine; and that platter, together with some flowers at her feet, was her only attire.

O selo de cinco dólares, não tanto:

This one was relatively uninteresting, by comparison—just a map. It showed several small islands set down in an expanse of water labeled, in neat letters, Sea of El Dorado. I assumed that the islands represented the Federated States of El Dorado itself, and that the little dot on the largest, marked by the word Nirvana, was the capital of the country.

Apenas por diversão, Morks coloca um selo do El Dorado em uma carta para seu amigo Harry em Boston. Enquanto ele está procurando por um carimbo regular para colocar com ele, a carta desaparece. Assim como ele está prestes a desistir de procurar, ele recebe um telefonema:

It was Harry Norris, calling me from Boston. His voice, as he said hello, was a little strained. I quickly found out why.

Three minutes before, as he was getting ready for bed, the letter I had just finished giving up for lost had come swooping in his window, hung for a moment in midair as he stared at it, and then fluttered to the floor.

The next afternoon, Harry Norris arrived in New York. I had promised him over the phone, after explaining about the El Dorado stamp on the letter, not to touch the others except to put them safely away.

Eles tentam um experimento:

"I'll tell you!" Harry exclaimed at last. "We'll send something to El Dorado itself!"

I agreed to that readily enough, but how it came about that we decided to send, not a letter, but Thomas à Becket, my aged and ailing Siamese cat, I can't remember.

Eles colocam o gato em uma caixa com buracos, endereçam-no a um endereço inventado ( Sr. Henry Smith, 711 Elysian Fields Avenue, Nirvana, Estados Federados de El Dorado ). um selo de 50 centavos e observe o que acontece:

For a moment, nothing whatever happened.

And then, just as disappointment was gathering on Harry Norris' countenance, the box holding Thomas à Becket rose slowly into the air, turned like a compass needle, and began to drift with increasing speed toward the open window.

By the time it reached the window, it was moving with racehorse velocity. It shot through and into the open. We rushed to the window and saw it moving upward in a westerly direction, above the Manhattan skyline.

And then, as we stared, it began to be vague in outline, misty; and an instant later had vanished entirely.

O gato volta:

Outside the window was the package we had just seen vanish. It hung there for a moment, then moved slowly into the room, gave a little swoop, and settled lightly onto the table from which, not two minutes before, it had left.

Harry and I rushed over to it, and our eyes must have bugged out a bit.

Because the package was all properly canceled and postmarked, just as the letter had been. With the addition that across the corner, in large purple letters, somebody had stamped, RETURN TO SENDER. NO SUCH PERSON AT THIS ADDRESS.

"Well!" Harry said at last. It wasn't exactly adequate, but it was all either of us could think of. Then, inside the box, Thomas à Becket let out a squall.

I cut the cords and lifted the lid. Thomas à Becket leaped out with an animation he had not shown in years.

There was no denying it. Instead of killing him, his trip to El Dorado, brief as it was, had done him good. He looked five years younger.

O sucesso com o gato os encoraja a enviar-se pelo correio ao El Dorado, endereçado ao General dos Correios. Harry vai primeiro. Morks muda de idéia depois que ele olha em um atlas e descobre que não existe tal lugar na Terra como os Estados Federados de El Dorado. Em vez disso, ele usa o último selo para enviar a sacola de Harry atrás dele:

I got up and fetched Harry's bag. It was summer, luckily, and he had brought mostly light clothing. To it I added anything of mine I thought he might be able to use, including a carton of cigarettes, and pen and ink on the chance he might want to write to me.

As an afterthought I added a small Bible—just in case.

Then I strapped the bag shut and affixed the tag to it. I wrote Harry Norris above the address, pasted that last El Dorado stamp to it, and waited.

In a moment the bag rose in the air, floated to the window, out, and began to speed away.

Talvez talvez "A Carta de Amor" de Jack Finney, publicada pela primeira vez em 1959? Tem alguma semelhança.

Resumo do enredo :

In 1959, Jake Belknap, a young, lonely, single man in Brooklyn, New York is looking for used furniture to furnish his recently acquired apartment. Walking in a section of the borough that contains very large, ancient, magnificent mansions about to be torn down, he finds a yard sale of antique furniture from a mansion about to be demolished, and is fascinated by an antique roll-top desk from the 1800s, which he purchases.

After getting the desk home, he opens a drawer and finds original stationery from the previous century, along with several old stamps from that period. He also finds a love letter from a woman named Helen Elizabeth Worley, who lived in the Brooklyn of the 1880s, to a man whom she dreams about, although she is about to be engaged to man she doesn't love.

Enchanted with the letter, he feels compelled to answer Helen, by writing to her using the old stationery, pen and ink, and putting an 1869 stamp on the letter (from his collection) and mailing it at the old "Wister" post office, which has been around since the 19th century in Brooklyn, unchanged by time.

He returns home and opens the second drawer, to find to his shock, that Helen has received his letter, and she wishes to know who he is and why he has written to her. He writes her another letter, describing who he is, and the fact that he lived in the year 1959 and although they have fallen in love with each other, to meet is impossible because of the years between them. Expecting to receive a final, long love letter from her, he is surprised to find in the bottom drawer, only her picture and the inscription "I will never forget".

After doing research on her whereabouts, he finally finds her grave in a local cemetery, and on her tombstone is engraved, "I never forgot". Miss Worley had died in 1934.

Texto completo aqui .