Is it really reliable to pass books by flying pigeons in ancient times?

There is often such a scene on TV: the protagonist receives a book from his subordinate flying pigeon and then starts planning. In ancient times, due to inconvenient transportation, there were some delays in the transmission of news. So the flying pigeon book is really credible and will not be hijacked? Pigeon is a common messenger in ancient times, but it is a one-way messenger, because it can only be sent from one place to another, and it can only be sent, but it can't return home. The sender will write the letter and tie it to the pigeon's leg, and then let them fly to the recipient's residence, so that the information can be transmitted.

So why can pigeons be used to deliver letters? This is mainly due to the homing of pigeons, which is different from other animals. Animals with this temperament, such as ants, can know their own way home, even if they are far away, they will find their way home because of their own habits. They have a geomagnetic compass in their mouth, so they can easily feel the earth's magnetic field. During the flight, their mouths are equivalent to navigators. Zhang Jiuling, the prime minister of the Tang Dynasty, kept pigeons at home and often used white pigeons to communicate with his close friends. Travelers from afar will also send a homing pigeon to their families to show their happiness and situation. Flying pigeons passing books is generally something that literati like to do, right? Flying slaves? Once and for all, pigeons are expensive to keep in captivity. If it weren't for the prime minister's family, ordinary people wouldn't choose such an elegant way to send letters. Civilians are usually more willing to tell their families through news.

So is it reliable for pigeons to deliver letters? Flying pigeons have great limitations in passing books because pigeons can only fly in one direction. If you want to get a reply, you need to buy homing pigeons locally, so that homing pigeons can fly back to the local area. It is also unsafe for flying pigeons to pass books, because pigeons themselves are very weak in nature and are easily captured by large animals, so information will not be transmitted on time; And the weather. After all, it is a pigeon. Even if you fly carefully, you will inevitably damage the writing paper. If it is windy and rainy, the letter is likely to get wet and the handwriting is not clear. The ancients usually used fast horses when they encountered military intelligence or emergency information. People often say that people ride fast horses and run all the way to deliver letters. It feels like a postman now, but roads and cars are much better than in ancient times.

If you want to whip quickly, you must have a post office, horses and accommodation. There will be a post station every once in a while, where you can stop for a while, drink water to quench your thirst, and then continue to ride a horse to deliver letters. Therefore, this is a very hard work. Building a post station in ancient times required a lot of money and manpower, especially when productivity was low. The delivery of letters is also divided into priorities, such as the military situation ahead, which must be delivered day and night. It can't be delayed. After all, it is a military incident, and the emperor has an imperial edict, which cannot be ignored. Then, just like some home letters, it is relatively slow, the roads are muddy, the weather is changeable, and the delivery time of letters is inaccurate. It may be three or five days, half a month or even three or five years.