TOEFL Integrated Writing Practice Test 036Roman Navy

Over 2,200 years ago, the Roman navy launched an attack on the Greek port city of Syracuse. Ancient historians claim that the Greeks defended themselves using a remarkable weapon known as a “burning mirror.” This device was said to be a polished copper surface, curved in such a way that it focused the Sun’s rays onto Roman ships, setting them on fire. However, there are several reasons to doubt this account, leading many to believe that the story of the burning mirror is likely a myth, and the Greeks of Syracuse never constructed such a device.

Firstly, the technological capabilities of the ancient Greeks likely were not advanced enough to create such a mirror. To focus sunlight intensely enough to set ships ablaze, the mirror would need to be several meters wide and have a precise parabolic curvature—a shape derived from geometry. The ability to produce a large copper sheet with these exact specifications was beyond the technology available in the ancient world.

Secondly, even if the Greeks had been able to create such a mirror, it would have been extremely inefficient in practice. In modern experiments designed to test the feasibility of a burning mirror, it was found that concentrating sunlight on a wooden target 30 meters away took around ten minutes to ignite the object. During this time, the target had to remain perfectly still, which would be highly unlikely in the case of moving Roman ships. This makes the burning mirror impractical as a weapon.

Lastly, there is little reason for the Greeks to have developed the burning mirror at all, considering they already had an effective weapon for setting ships on fire—flaming arrows. The burning mirror and flaming arrows would have had a similar range, so the Greeks would have had no advantage in using the mirror over the much simpler and readily available flaming arrows.