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Nauscopy: The Art of Detecting Ships on the Horizon at Impossible Distances


Frenchman Étienne Bottineau invented the now-forgotten science that allowed ships to be seen that could not even be seen with a telescope.

In the history of extraordinary abilities, that of one Étienne Bottineau deserves a place of honor. Bottineau was a lesser member of the French naval engineering corps in the second half of the 18th century and who would not have earned a place in history if it had not been for his unusual talent: of being able to predict the appearance of ships a long way from shore and all by simply studying the line of the horizon.

Bottineau was able to see ships at a distance of between 300 and 900 miles from the coast, and which no radar or telescope of the time were able to see. Before being recruited by captains of war, this engineer had become famous among sailors because he spent hours in the taverns of Mauritius (known then as “Île de France”) betting on the number of ships that would approach the island’s coast. By simply observing the horizon he could not only discern how many ships there were, but also say with certainty how far apart they were and estimate their navigation range and tonnage. Thanks to that signature fame among seamen, he was called to the French Imperial Court and spent more than eight months being put to the test, successfully predicting the arrival of English enemy fleets and facilitating his country’s victories.

During this period he managed to convince his captains that his discipline was genuine. He insisted, against the natural suspicions, that his predictions were not an act of witchcraft or the result of good luck; but rather that they were the product of rigorous observation during years of trial and error. Bottineau claimed to be the inventor of a new science, which he called nauscopy: “the art of discerning ships and land at great distances.” Open water

But Bottineau did not appear to be in any hurry to explain nauscopy; perhaps because he wanted to remain as the world’s only nauscopian, or because his explanation was as strange as the extravagance of his practice. Obviously, not clarifying the technique behind the phenomenon brought some inconveniences (suspicion of his use of witchcraft, for example), until the naval officers decided to offer him money for his secret.

Bottineau’s explanation was fascinating (albeit extremely ambiguous): “Each boat produces “emanations” in the ocean. These emanations affect the transparency of the atmosphere. Therefore, meteorical effects [as he called them] are produced on the horizon and they can be seen and read by all men who know how.”

His theory states that it is possible for the trained eye to discern the approach of ships hundreds of miles away because they affect the atmosphere around them. Something very similar to the theory of the magnetic field, which states that an object affects, on an energy level, the atmospheric zone within its vicinity. Bottineau perceived those “emanations” or magnetic changes as nobody had before him, and nor has done since. And the testimony of his predictions during eight months in the war verify him as one of the most extravagant visionaries there has ever been.

His explanation was not sufficient for the naval ministers, however, and he was dismissed as “hallucinatory” and history quickly forgot him. But we can ascertain that Bottineau spent many hours of his life watching and studying the horizon and that it revealed itself to him. And in the process of his exercise, which has fortunately been documented, he gave birth to one of the most beautiful paradoxes of humankind: the possibility of generating an intimacy with distance.

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