Periboob

Periboob is a low-cost maritime decoy whose value lies less in what it can damage than in what an enemy believes it has seen. A sectioned, oil-drum-like device with a tall tube and a magnetic trigger, it was designed to exploit the fear of an unseen underwater threat and draw enemy forces into reacting to something that was not there.

Design and Operation

The device was sectionalized and resembled an ordinary oil drum, with a tube projecting twenty feet above it. A simple magneto-sensitive mechanism controlled its behavior. The design was practical as well as deceptive: the whole device could be mass-produced at low cost, making it possible to create a threat across a wide stretch of ocean without relying on a small number of elaborate weapons.

In the water, a Periboob floated with its nozzle and four to six feet of tube visible above the surface. When a mass of steel or iron came within four hundred yards, it sank out of sight; when that mass moved away, it rose again until the tube protruded above the waves. The movement made the decoy responsive to nearby ships, giving a plain floating object the appearance of something that reacted to their presence. Its physical modesty was part of its usefulness: an oil-drum shape could conceal a mechanism whose significance depended on the observer’s interpretation.

Staging the Threat

The deception required more than a device. It needed what the account calls a prepared stage and a spotlight. The stage had been arranged from the outbreak of war by allowing the enemy to obtain top-secret plans. The plans made the decoy part of an intelligible threat, while the sight of it at sea could give that threat a visible, apparently immediate form. The setup thus joined concealed preparation to public evidence: the enemy could encounter an object whose meaning had already been prepared for it.

The spotlight was supplied by a convincing bang and the sinking of a couple of merchant vessels at sea. In this sequence, the explosion and the losses made the supposed danger seem consequential rather than theoretical. The device did not have to destroy ships itself to serve the scheme; the staged circumstances around it could encourage observers to connect a visible tube in the water with the apparent evidence of maritime attack. The resulting impression was meant to aggravate the enemy and turn its attention toward a danger that was not what it appeared to be.

Phase Nine and Enemy Reaction

The sudden switch from Phase Four to Phase Nine led to the inference that an approaching Terran spaceship must be carrying a load of Periboobs to scatter through the world’s oceans. That shift gives the device a place within a larger campaign: it was not merely an isolated piece of hardware, but cargo for a broad operation in which the ocean itself could be made to seem dangerous. The emphasis on scattering them suggests scale, while their low-cost construction made that scale plausible.

The planned response extended beyond any single sighting. The enemy would patrol the oceans and bomb Periboobs wherever it found them. The decoys could therefore draw ships and weapons into searching for, attacking, or otherwise expending effort against false targets. Their strategic force rested on that diversion: the enemy’s own precautions could become part of the effect, keeping attention fixed on a threat the decoys represented rather than a real submarine at each point of suspicion.

Deception Without Secrecy

The scheme’s most striking feature is that it did not depend on the deception remaining undiscovered. The enemy could trawl a Periboob from the depths and learn that it had been fooled; even that recognition did not undo the work already done by the sighting, the staged evidence, and the response it had prompted. The decoy’s success was therefore not measured solely by whether an individual object passed indefinitely as genuine. Its larger purpose was to provoke an aggravated enemy into striking at what was not there.

That reversal distinguishes Periboob from a conventional weapon. Its tube and magnetic mechanism give it a concrete, repeatable behavior, but its decisive effects occur in enemy judgment and deployment. The account makes the ocean a prepared scene in which objects, explosions, documents, and military reactions reinforce one another. Periboob embodies that method in miniature: inexpensive to manufacture, visible enough to invite interpretation, and useful even when the adversary eventually recognizes the trick.