Chapter 253

Little known.

In ancient times, the yield of land was not high. In addition to the problems of limited output caused by war, natural disasters and poor types of crops, there was also a very key reason.

That's because there was no chemical fertilizer in ancient times.

The fertilizers used in ancient China were basically farm manure with very extensive and low nutritional density.

That is, human and animal excrement and urine. At most, add some long-term fermentation process, which is commonly known as retting.

But it's worth mentioning.

Even such a simple and crude early means was first used by us in many ancient dynasties.

When our ancestors worked hard with a burden on the horizon, the ancient dynasties in the West looked blankly at the excreta in the city and didn't know how to deal with it.

In the middle ages, Europeans' habit of throwing dung freely lasted for hundreds of years and remained unchanged until the 12th century, which also provided a comfortable hotbed for the spread of the black death.

Otherwise, how do you think high heels and perfume are invented? (there is a book called the middle ages with flavor, which is written by foreigners themselves. If you are interested, you can go and have a look.)

Throughout the history of the world, the ancient Greek Minoan civilization has the same drainage and drainage system as ours - and it has to be said that the Minoan civilization has a good water conservancy foundation.

In ancient times, we can say that we are better than the Song Dynasty. It is difficult to find those who can break their wrists with him in other dynasties.

In fact, you can also find a few examples of civilizations that are similar to our development at a certain node, or even superior in some aspects, but they have been dated without exception.

The reason why Chinese civilization ox x is not that it is always the world