"The Fires Within" (as by E G O'Brian) (short story): Aliens that are not aliens!

Asimov's "The Gods Themselves" is probably the only other story I have read that can compare with this in inventiveness of unfamiliar life forms in fiction.

From the facts cited, this story was obviously written when much less was known about the interior of earth. But that doesn't dilute the fun of the story.

Story summary.

Most of the story is told in flashback. So let's begin with flashback.

A professor has a brainwave: cannot we use sonar (acoustic reflections) to "see" what lies beneath the surface of earth.

He builds a device that lets you "see" on a display what lies at any depth under the surface of earth. Oh, maximum depth depends on power input; the maximum the professor ultimately reaches is a couple of tens of miles.

Initially, the device is a curiosity. Then it becomes a useful industrial machine - very interesting for geologists. And then comes the inevitable twist in the tale.

It is obvious that as you go deep into earth, the pressure of rocks above grows, & also the temperatures increases. 10 miles down both are unbearably huge.

When the device was first tested, they found a lot of dead earthworms. Obviously they were killed by the energy released by device.

OK - so here is the twist. Professor is expecting that more than a few miles down, you will not really see any features - cavities would have been filled in, & it will be all molten rock. And that is what he sees, until he reaches a certain level - some 10 or 12 miles down.

What is seen are huge physical features where none are expected. Some investigation later, it is clear that they cannot be natural. Some theorizing later, the conclusion is: obviously there are intelligent beings living in that seething mass, & that they can float through all that rock, & build their cities there!

Rest of the story is told by the intelligent beings living down under, in the hot underbelly of earth - 300 years later. Oh, yes, & they are tentacled - Clarke's favorite feature in unfamiliar life forms.

Looks like they always thought no life could have (obviously) existed on the surface of earth since it was near vacuum & so cold it was near absolute zero (compared with their environment)!

Until they detected these sonars probing down under. That is when they tried making contact with the fragile humans. The tone of ending says that meant the doom of humans - they could never withstand the heat these creatures brought up.

End is worried musing by one of their own - they live only 12 miles deep. What happens if they should be contacted by anything living below them?

Collected in.

1. "The Collected Stories of Arthur C Clarke"
2. "Reach for tomorrow"
3. "Of Time and Stars"
4. "Across the Sea of Stars"

Fact sheet.

First Published: Fantasy, August 1949, under the pen name "E G O'Brian".
Rating: B