I enjoy reading about famous, historical personages of math and science. Some of these individuals were egoists and some were real people. I think the naval use of mirrors is attribuated to Archimedes and later written about by Diocles. The following has been taken from two longer web articles.
Diocles (240BC - ~180BC) in
Burning Mirrors , proved that the surface that reflects the rays from the Sun to a single point is a paraboloid of revolution. Constructions of such devices remained of interest as late as the 6th century AD, when Anthemius of Tralles, the architect of the Hagia Sophia at Constantinople, compiled a survey of remarkable mirror configurations.
According to Roman writers who chronicled the life of Archimedes (287BC – 212BC), the mathematician was a devoted subject of Hiero II, ruler of Syracuse, and spent part of his career designing and building weapons to defend Syracuse -- catapults, pulley hoists and levers for disabling enemy ships and siege towers. … Some Greco-Roman historians also assert that during the Roman siege of Syracuse from 214 to 212 B.C., at the height of the Second Punic War, Archimedes used bronze mirrors to focus sunlight on Roman ships and set them on fire.
The burning mirrors are mentioned by Lucian of Samosata and Galen. Anthemius of Tralles (534), the Architect of the Hagia Sophia, tells us that Archimedes used many mirrors. Johannes Zonaras in 1118 says that first Archimedes used the "iron hand" against the ships and then he burned these with mirrors.
http://www.mlahanas.de/Greeks/Mirrors.htm Plutarch writes in his work on Marcellus, the Roman commander, about how Archimedes' engines of war were used against the Romans in the siege of 212 BC:
... when Archimedes began to ply his [war] engines, he at once shot against the land forces all sorts of missile weapons, and immense masses of stone that came down with incredible noise and violence; against which no man could stand; for they knocked down those upon whom they fell in heaps, breaking all their ranks and files. In the meantime huge poles thrust out from the walls over the ships and sunk some by great weights which they let down from on high upon them; others they lifted up into the air by an iron hand or beak like a crane's beak and, when they had drawn them up by the prow, and set them on end upon the poop, they plunged them to the bottom of the sea; or else the ships, drawn by engines within, and whirled about, were dashed against steep rocks that stood jutting out under the walls, with great destruction of the soldiers that were aboard them. A ship was frequently lifted up to a great height in the air (a dreadful thing to behold), and was rolled to and fro, and kept swinging, until the mariners were all thrown out, when at length it was dashed against the rocks, or let fall. http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Archimedes.html Pete
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