In the Northern Song Dynasty, people made 叆叇 (ai dai) of crystal, ivory and gold wire. It is the ancient version of "childrens eyeglasses", shaped like the cat's eye on the security door.
During the Yuan Dynasty, the prototype of modern glasses was introduced into China from Europe, and was popular among the royal family and the wealthy areas of Jiangnan. At that time, glasses had no legs and had to be held by hand in front of the eyes.
In the Ming Dynasty, in order to facilitate the use of glasses, people installed the back of the head tie, forehead support and so on.
Until the late Ming and early Qing dynasties, glasses could be customized, and different colors of lenses appeared. Emperor Yongzheng collected nearly 100 pairs of glasses of different colors, and there were many folk workshops for glasses.
People can't breathe in when they're talking!
To speak, you first need to breathe in air, and then pull the vocal cords in tight, exhaling air will vibrate the vocal cords to produce sound. But the vocal cords are open when you inhale, so vocalizing and inhaling cannot happen at the same time.
Scientists at the Massachusetts Institute of Technology have found that a brain circuit in the brain stem region, which controls the rhythm of breathing, regulates the priority between speaking and breathing, ensuring that speaking and breathing do not conflict and prevent people from choking to death while speaking.
- Every 2.4 million years, Mars heats up the Earth
Mars' gravitational pull on Earth is generally thought to be only one millionth that of the sun's. | pixabay
Australian scientists studied nearly 300 deep-sea sedimentary rocks around the world that were formed more than 65 million years ago, and according to the shape of the sedimentary rocks, the strength of the Earth's ocean currents changes every 2.4 million years.
Scientists say the change has to do with the orbits of Mars and Earth. The Earth periodically gets closer to the Sun because of the gravitational pull of Mars, and thus receives stronger solar radiation, causing the climate to warm and the ocean currents to strengthen, and such changes occur every 2.4 million years. However, the current global warming is mainly related to greenhouse gas emissions.
- Australian tycoon announces Titanic reconstruction
In the early hours of April 15, 1912, Titanic, then the world's largest and most luxurious passenger ship, collided with an iceberg on its maiden voyage and sank forever at the bottom of the Atlantic Ocean | Blue Star Line
Recently, Australian mining magnate Clive Palmer held a press conference at the Sydney Opera House to announce that the Titanic would be rebuilt.
In fact, this is the third time he has announced that the passenger ship will be rebuilt. In 2013, he held a news conference in New York to announce plans to invest $500 million (about 3.6 billion yuan) to build Titanic II. But after two years of construction, the project was dead. In 2018, he announced the resumption of the Titanic II project, with a target of 2022 for its maiden voyage. However, the outbreak of the new coronavirus has led to the closure of many shipbuilding factories for a long time, and the project has been stranded again. This time, Clive said to achieve the first flight in June 2027, hope all goes well...
- Darwin was wrong!
In his 1871 book The Descent of Man, Charles Darwin noted that males in most species are stronger than females. But a new study from Princeton University suggests Darwin was wrong.
The scientists found that in about 45 percent of mammals, males are stronger than females, but in 39 percent of mammals, males are the same size as females, and in 16 percent of mammals, females are stronger than males. Thus, among mammals, males of most species are not stronger than females.
