The sniper starts from the bright sword escape period

Chapter 405 The front of the car, the four-wheeled carriage
In fact, if we are serious, there were still four-wheeled carriages in the Ming Dynasty, but because the four-wheeled carriages in the East could not solve the problem of turning, they were never popularized, and only four-wheeled carriages without steering systems were used on a few occasions. It's just a carriage.

But unlike the East, the West has four-wheeled carriages very early.During the period of the Roman Empire, there was already a very complete steering four-wheeled carriage, with steering mechanisms, shock absorbers, and brakes.

From the four-wheeled carts pulled by oxen on the Qingming Riverside Map, there is no special steering device.Even judging from the surviving cultural relics of ancient four-wheeled vehicles in China, there is indeed no special steering device.The restored one with steering device and shock absorbing device is an ancient Roman four-wheeled vehicle. There is a hub connected to the chassis in the middle of the common shaft of the two front wheels. The common shaft of these two wheels can rotate around this The central hub rotates at a large angle, so that the four-wheel vehicle can turn more conveniently.The structure of this four-wheel vehicle is similar to the four-wheel trailer structure of a car.

According to archaeology, the four-wheel steering device may have originated from the Celts in BC, and the Romans learned and developed it, which greatly improved the performance of the carriage.By 200 A.D., sturdy Roman carts rumbled down the avenues, horse-drawn mail and coaches stopping to change horses and moving on, traveling 24 kilometers every 160 hours.

The slow-moving ox cart can still withstand the bumps on the roads of ancient times.If it is replaced by a few horse-drawn carriages with fast horses, the degree of bumps will be unimaginable. People cannot sit in a galloping carriage, and perhaps they can only stand on the carriage to alleviate the degree of bumps.The appearance of the four-wheeled carriage made shock absorption possible. Although there were no springs at that time, people could set the cowhide pulling mode to absorb shocks. This was an innovative technology of the Romans.

From the partial map of the restored Roman carriage, it can be seen that the carriage is in a suspended state, which can significantly reduce the intensity of horizontal shaking. The cowhide also has a certain degree of elasticity, and the vertical direction also has a certain shock absorption effect.This gives the four-wheeled carriage a certain degree of comfort.Coupled with the 40 kilometers of road system built by the Roman Empire, [-] kilometers of it were paved with stone.Along the road, the Romans also built the earliest post system, providing board and lodging and carriage hire services.These post stations not only serve the military, but are also open to ordinary tourists.These measures brought about the prosperity of Roman carriages.

With the increase in the application of steel, springs were born, which brought about a revolution in the shock absorption of carriages, and two-wheeled carriages can also be easily shock-absorbed.

Although the steering device and shock absorbing facilities of the four-wheeled carriage have a long history and there are extensive exchanges between the East and the West, it is a pity that this technology still came to the East at a later time.

Putting a shoe on the horse's shoe not only protects the horse's hoof, but also makes the horse's hoof grip the ground more firmly, so that the horse has a stronger running ability, which is very beneficial for riding and driving.The horseshoe may have been a Roman innovation, and it is common at sites from the 1st century BC.

Although the horseshoe originated in the west, it quickly spread to the east, which is obviously different from the situation of the four-wheeled carriage.The appearance of horseshoes naturally obviously promoted the prosperity of the carriage, and its ability to cavalry troops was also greatly improved. This is naturally a far-reaching matter, and the rise of the Mongol Empire is related to this.

Strange "horse sandals" were also common in Roman times.It is a smooth iron disk bent into a ring at each end.Apparently it was attached to the horse's hoof, no doubt to protect it.A few "horse sandals" have spikes that help the horse grip the ground.It may be applied on cobblestone roads or other muddy and rough surfaces.

Because the two-wheeled carriage is in close contact with the horse through the shaft, it can be braked by the horse.The horses of the four-wheeled carriage only play the role of traction, and braking facilities are naturally essential.The brakes on the rim can be braked with your feet, which ensures the safety of the four-wheeled carriage.

Although it is only a small steering system, it brings a very big gap. You must know that the first car placed the engine directly behind the carriage, and used the rear wheels of the carriage as the driving wheels. powering it.

If Dongfang is still using two-wheeled carriages, it is obviously not so easy to place the engine on the two-wheeled carriages for use.

What's more, the most important contribution of the four-wheeled carriage is to provide a reference for the steering of the four-wheeled vehicle.

In fact, the most significant difference between a two-wheeled carriage and a four-wheeled carriage is the use of horsepower. Because the four-wheeled carriage has four wheels, the weight of the goods on the carriage is borne by the four wheels.

Therefore, what the horse provides is only traction, but the two-wheeled carriage is different, because it is the reason for the two-wheeled carriage, so the horse must bear some weight from the goods in the carriage to ensure the stability of the two-wheeled carriage.

Such an approach would naturally greatly consume the horse's physical strength, which would naturally limit the load capacity of the two-wheeled carriage.

However, two-wheeled carriages also have some advantages, such as a small turning radius. For example, in the period when this bearing has not yet appeared, it can greatly reduce the pulling force required by horse-drawn carriages. After all, two-wheeled carriages only have two wheels to produce sliding friction. A four-wheeled carriage has four wheels that generate sliding friction.

However, the bearing is a trivial matter for Bailixiu. He just found a thicker iron plate, and then used the indestructible Xingyun carving knife to draw two rings, one large and one small, on the iron plate. The next step is to draw several small rollers, so a roller bearing is done.

As for the precision, with the blessing of super precision, the bearings made by those high-precision machine tools are not as accurate as the bearings made by Bailixiu.

As for the shock absorption of the four-wheeled carriage, Bailixiu didn't pay that much attention. He just used some thick bamboo instead. It was no longer considered by Bailixiu.

Hesitation Time is in a hurry, and there are no good materials, so Bailixiu didn't put too much decoration on the four-wheeled carriage.

But when Bai Lixiu appeared at the gate of Jinling City in a four-wheeled carriage, the soldiers guarding the city were still shocked.

Since more than a dozen pieces of glass half a person's height need to be placed, and the glass cannot be stacked directly but must be placed vertically, so Bailixiu's four-wheeled carriage is not small, at least in terms of size. The size of four ordinary two-wheeled carriages.

Of course, the defenders were not only surprised by the carriage, but also by the mirrors placed vertically on the carriage!

After all, for the sake of simplicity, Bailixiu's four-wheeled carriage only used four wooden pillars to support a roof, and there were no wooden boards around it to cover it, so the mirror inside could be seen clearly.

However, one of the men dressed in Jin Yiwei took the portrait in his hand, looked at Bai Lixiu, and asked:
"Is this son Bailixiu who sells rocking chairs across from Matchmaker Cai in the north of the city?"

(End of this chapter)