There were no measuring instruments in ancient times. How did the ancients distinguish between lakes and oceans?

Although the ancients didn't have measuring instruments, they had eyes and tongues, through which they could taste the lake. Besides, the lake can be seen as far as the edge, while the ocean is endless and very vast, so it is very easy to judge the lake and the ocean. Even if the lake is very big, then this person can measure it step by step with his own feet. As the saying goes, a journey of a thousand miles begins with a single step. Even if the lake is big, it can't be so big that China doesn't have such a big lake. Therefore, although the ancients did not have measuring instruments, they could easily judge what a lake was and what an ocean was in their daily lives.

In our daily life, we are often full of all kinds of curiosity about our world. For example, our earth is called water polo. The reason for this is that more than 70% of the earth's area is covered by some waters, and the land area only occupies three floors. Therefore, when we look at our earth from outer space, we will find that our earth is really a planet rich in water resources. However, most of these water resources are oceans, and only a few are freshwater basins, which are what we call lakes and rivers. Moreover, the distribution of these oceans also has an obvious feature, that is, they are generally distributed in coastal areas of continental plates.

This leads to the combination of land plate and ocean plate, and there is also a scientific hypothesis between land plates, that is, the theory of continental drift. So in these numerous rivers and seas, there is a difference, that is, most of the water in these lakes on land is fresh water, and only a few are shallow lakes, but we can see their colors, which are still relatively clear. The ocean gives us an unfathomable feeling. The color of the ocean is blue. Besides, its water is salty, which is one of the most important differences between lakes and oceans. It can be judged by human senses.

To sum up, even without measuring instruments, people can still feel everything in nature with their own body senses. It is because of the continuous practice of the ancients that so many beautiful lakes in China were discovered, such as Dongting Lake and Poyang Lake, which gave birth to early human civilization. Together with these oceans, these lakes constitute the land-sea cycle on the earth, which makes the precipitation on our earth cycle back and forth, and also makes us human beings thrive.