Caius Sergius Orata (fl. c. 95 BC) was an Ancient Roman merchant and hydraulic engineer.
Sergius was well known to his contemporaries for the breeding and commercialization of oysters, of which he was a noted innovator. Orata wanted to take advantage of the Romans' liking for shellfish as food, so he developed many new techniques for breeding oysters. This included the practice of surrounding mature oysters with twigs, to which their young (known as "spats") could affix themselves and thus be easily transplanted wherever desired. This allowed for the creation of artificial oyster beds, which he surrounded with channels and dams in order to protect them from the sea tides.
His activities of this type at the Lucrine Lake in Campania, adjacent to the luxurious and popular spa town of Baiae brought him into conflict with the local Roman tax farmer Consilius, in a dispute over this use of the public resource of the lakefront. Consilius was successfully defended in this case by the orator Crassus. As Orata was also a significant developer and builder of costly villas in the area, Crassus made a joke based on the common use of terra cotta tiles both as surfaces for artificial oyster beds and also in the roofs of structures, saying that "even if Orata were deprived of the waters of the lake, he would still find oysters on his roof-tiles".
Orata was also credited by Vitruvius with the invention of the hypocaust (underfloor heating), although this is not fully confirmed. What seems certain is that he invented a type of hanging baths ("balneae pensiles"), some kind of relaxing thermal baths; they are usually considered to be hypocausts. He commercialized them as successfully as the oysters.
Sergius Orata became rich due to his inventions; he was distinguished for his love for luxury and refinement. "The Orata," Festus noted, "is a kind of fish so called for its golden color (aurata, "golden," also spelled orata). ... Because of this, it's said about the very wealthy Sergius that they called him orata, because he wore two big rings of gold. Some authorities assert that his nickname just comes from the commercialization of those fishes."
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