6,000-year-old ignitor world’s oldest solar device

During the sixth century BCE, Confucius wrote about the common use of curved mirrors shaped from shiny metal to concentrate the rays of the sun for making fire. These became known as yang­­-suis ­­– translating to solar ignitors, or burning mirrors.



According to the great philosopher, upon waking up the eldest son would attach a solar ignitor to his belt as he dressed for the day. It was his duty to focus the solar rays onto kindling to start the family’s cooking fire.

According to another early text, the Zhouli, which describes rituals dating far back into Chinese antiquity, “The Directors of the Sun Fire have the duty of transferring with burning mirrors the brilliant flames of the sun to torches for sacrifice.”

Although scholars found over the years many ancient texts discussing solar ignitors, the discovery of an extant yang sui eluded them for centuries. Quite recently came the Eureka moment. Digging up a tomb that dated to about three thousand years ago, a team of archaeologists found in the hand of a skeleton a bowl-shaped metal object. While the inner side could have passed for a wok, the exterior trough had a handle in its center. That’s what caught the eye of the two archaeologist in charge of the dig, Lu Demming and Zhai Keyong. They immediately brought the relic back to the local museum and ordered its specialists to make a mold from the original and then cast a copy in bronze.



After polishing its curved surface to a high degree of reflectance, the inquisitive archaeologists focused sunlight onto a piece of tinder just as the eldest son would have done so many years past, and in seconds the combustible material burst into flames. “This verified without a doubt that the purpose of the artifact is to make fire,” Lu and Zhai later wrote, assured of having found the oldest solar device in the history of humanity.


Now that the world could see what a real yang-sui looked like, museums retrospectively identified 20 more previously unclassified objects as solar ignitors.


http://www.rawstory.com/rs/2014/06/06/6000-year-old-ignitor-worlds-oldest-solar-device-author/