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Bewildering Stories

Challenge 669 Response

The Sacrificial Camera

with Elous Telma

In Elous Telma’s “The Sacrificial Camera”:

  1. What is the water pressure at the bottom of the Aquarium? You may calculate it in any units you like.
  2. What might the shark’s movements portend for anything else on the mysterious mound?
  3. How might the Disposable’s discovery relate to Frank’s hallucinations in “Frank’s Sea Visions”?


For every 10 meters of the sea water column you get roughly one atmosphere of pressure. At 2 kilometers deep, liquid pressure is approximately 200 atmospheres.

If you want to be more accurate, because salty water is a tiny bit denser than distilled water (which is used for these idealized calculations), you may want to add a few more atmospheres (depending on the precise quality of sea water). Typical sea water has a density of 1.03 times that of distilled water. That adds about 6 atmospheres in total, for the two kilometers of depth.

Further, you should also add one more atmosphere, which is due to the column of air above the sea surface pushing down onto the water surface.

Put together, that makes the total pressure at the bottom of the Aquarium (just over the brine lake) approximately 207 atmospheres.

That is enough to destroy a human instantly, of course. Not so a specially designed research Watermelon, though. A marine biology camera with some engineering could make it for a while, I suppose.

A shark? Some sharks are remarkable in how they can withstand different water pressures. The tiny cookiecutter shark (Isistius brasiliensis) appears able to daily migrate vertically 2-3 kilometers. No wonder Frank’s confused mind chose this shark species to infest his deep-sea visions.

Water pressure is a physical barrier for some animals but not for others.


We see the shark standing still or moving fast. When I do that, I’m usually in trouble. It’s me trying not to advertise my position and if my cover gets blown, then I’m out of there fast - speedy, jerky moves and all.


The team of humans have a good gut feeling for Nature. Also, they have considerable scientific knowledge. Frank knew of the brine lake discovery on Dioptra. He must have been instantly fascinated.

Just as dreams often incorporate our day’s conscious thoughts or yearnings in them, in some perturbed version, oftentimes, so do hallucinations. Frank’s mind is searching for a comforting place. To a seasoned sailor with a love of the sea and knowledge of a remarkable and unusual environment just two kilometers beneath his feet, the mind creates a unique version. The little humanoid may represent his need for human affection, which he hasn’t known to the extent he may have wished.

He cannot have guessed everything about the lake right, of course. But Frank’s dreams, despite their immense confusion and interference, have a fairly clear essence and serve as clues to what may be happening on the island. Nothing is served neatly on a dish and there are spines to pick out but, at the level that is reachable by our secluded characters, this may just have to do, for now.

Copyright © 2016 by Elous Telma

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