What does the wave of sand mean?

Liu Yuxi's "Langtaosha" in Tang Dynasty? Article 7 "refers to:

In August, the sound of the waves is like Ma Benteng's roar. Several feet high waves rushed to the rocks on the shore and were beaten back.

In a blink of an eye, I retreated to the intersection of rivers and seas and returned to the sea. The sand it rolls up is like a pile of snow in the sun.

Original text:

In August, the waves roared, and the head was several feet high, touching the back of the mountain.

In a blink of an eye, I arrived at Haimen, and the rolled sand was like a snowdrift.

Extended data:

Creative background:

This poem should be Liu Yuxi's later work. Since the Anshi Rebellion in the Tang Dynasty, the momentum has declined. Governors are independent, eunuchs are authoritarian. When talented people are released and angered, resentful works are produced. After Liu Yuxi was transferred from Beijing official to local official, he wrote "Langtaosha?" Seventh. "

Appreciate:

The first sentence, "August stormy waves roar", describes the trend of the tide coming in, from far to near, and uses a verb "roar" to highlight the feeling of the approaching waves. The second sentence is about the spectacular scene when the tide reaches its peak. The swift tide, with a body dozens of feet high, hit the cliffs on both sides. In a word or two, compared with "roaring to the ground" and "touching the mountain", it describes the whole process of the ebb and flow of the tide, and the sharp change of tone sets off the surging tide.

This poem changed from a dynamic description at the beginning to a static description after the tide receded. When the tide exits Haimen, the surging waves show their spirit in another form-the sand pile rolled up by the waves is like a snowdrift. Another spectacle left by the tide set off the spectacular scene of the August tide roaring into the mountains.

About the author:

Liu Yuxi (772-842), a native of Luoyang, Henan, called himself "Luoyang" and Zhongshan. The first one is Zhongshan, Wang Jing and Liu Sheng. A writer and philosopher in the Tang Dynasty, he was called a "poet". Representative works include Humble Room Ming, Zhi Zhu Ci, Yang Liuzhi Ci and so on.