Calamus Dews Can Improve One’s Vision


“Gatsby” is a college student at Stony Brook University in New York. He is also a rapper. During the pandemic, he was unable to complete his college courses in-person in New York, and particcipated in a Go-Local program at Southern University of Science and Technology (SUSTech), where he is taking several in-person courses, instead.

He shared the following folklore with me during an interview when we were having dinner together.

The Main Piece:

The dew from the leaves of Calamus is said to be able to improve a person’s vision.

Gatsby says he learned this during a class about archeology and ancient Chinese history. He says the professor of the class, Tang Jigen, invited a guest speaker who is an expert in china (the objects, not the nation), and also in Calamus (calamus is a kind of plant that is loved by many famous poets and authors in ancient China) . The guest speakers tells the students that in ancient times, calamus will be raised in very fine environment, and in early morning, they will be moved outside so that dew will form on the leaves, and the owners will collect the dew and use it as eyedrop because the dew is food for the eye.


This is very interesting. Scientifically, dew is just water, maybe even with small particles of dust in it. I don’t see how mere water can be good for the eye. However, I do find that the tradition Chinese medicine do include dew, and calamus dew is really recorded as being able to improve one’s eyes.

Regardless of whether it really is effective, I’d like to analyze why people believe so. To most people, especially ancient people who didn’t know that much about physics, dew is water that come out of nowhere. Unlike water from the lake or the sea, which is always there and dirty things might fall into it, and there’s mud at the bottom, dew suddenly appears from the air. You know where the water in the river come from: from the river. But you don’t know where dew come from. So, there’s no way dirty things can contaminate it, because it appears out of nowhere and is collected immediately.

Ancient Chinese people also have a strong feeling for plants. They like them, thinking that they smell good. Traditional Chinese medicine also believes that many of the plants and flowers, calamus included, can be taken as medicines. Therefore, whater that comes out of nowhere and sticks on beautiful plants that might be taken as medicine is considered to be the purest thing. That might be why people believe it is good for the eye.