In ancient times, there was no tolerance. How can a horse's wheels turn?

There were primitive bearings in ancient China, which were added with iron rings and animal fat. However, due to the level of science and technology at that time, ball bearings in the modern sense could not be made, so the friction force was much greater.

The invention of bearings is a great progress in science and technology, and it also provides support for the rotation of wheels and reduces friction. It is generally believed that modern bearings were invented by western scientists in 18 and 19 centuries, which effectively alleviated the friction problem of wheels.

But more than 3,000 years before the invention of bearings in the West, there were carriages in ancient China. If there is a carriage, there must be wheels, and if there is a wheel, there must be bearings, otherwise the chariot will not be killed, run or turn at all. Although I don't know when people invented the wheel. I don't know when people learned to use horses or donkeys to pull wagons forward.

But in the Xia Dynasty, there were already records of soldiers fighting in carriages. At that time, countries used carriages to pull troops to kill the enemy, thus forming a war convoy. When the chariot moves forward, the axle is connected with the wheel through the bearing, which reduces the friction of the wheel, and can fix the wheel at the same time to ensure that the wheel will not shake and fall off.

Before the Han Dynasty, the carriage was always a very important combat tool, so the ancients in China never stopped improving the bearings. Only at that time, there were no modern ball bearings, and wooden bearings, bronze bearings and iron bearings or bearings combined with wood and iron were used. These two iron rings, the big ring fixes the outer ring, the small ring supports the inner ring, and then coated with animal fat.

The reason why modern people don't know how the wheels of ancient carriages turn is mainly because the ancients couldn't make bearings, but that's all wet. As mentioned earlier, before the Han Dynasty, especially during the Spring and Autumn Period and the Warring States Period, chariots were the main weapons of all countries.

At that time, China was in the period of interaction between the Bronze Age and the Iron Age, and bronze bearings were mainly used. Mainly because the chariot soldiers were gradually replaced by cavalry, the use of bearings expanded from military to civilian. Probably from the Han Dynasty, the chariot soldiers disappeared.