"Then you're going to keep it a secret for me." Lu Jiu said seriously: "I still have to rely on this artifact to make money." ”

Fu Lanqing: "......" beauty is not eye-catching, and there is only money in my heart.

He was still very curious, and nodded very obediently: "Don't tell others, Ah Yuan won't tell you, help you keep it secret." ”

Lu Jiu patted him on the shoulder: "Very conscious!" ”

Then, let Fu Lanqing prepare a lot of things.

In fact, there is nothing, just prepare a lot of black cloth for Lu Jiu to experiment.

Water writing cloth is mainly made of cloth and is made according to the principle that the paint is transparent when exposed to water.

With black cloth as the medium, add a layer of environmentally friendly white paint treated by a special process on its surface, which has the effect of being transparent when exposed to water. The main ingredient of the paint is silica, which is the main ingredient of sand and the main raw material of glasses.

Transparency in water is mainly the physical principle of light reflection.

Because Lu Jiu will open a workshop to make glass in the future, the refining method of silica naturally cannot be known to Fu Lanqing.

He's so smart!

Lu Jiu directly bought a bottle of paint specially used to make water writing cloth in the system mall.

Now she is mainly experimenting with the kind of cloth in ancient times, which is most suitable for making water writing cloth.

Fu Lanqing's movements were very fast, and he got a lot of black cloth for Lu Jiu.

"Which one is better absorbent?"

Fu Lanqing didn't understand it, but the embroidery girl knew.

The embroiderer pointed to several of the fabrics.

Lu Jiu planned to start with these pieces of fabric, because the paint was limited, so Lu Jiu only painted a small piece of each.

The sun is not bad now, and if you wait for more than an hour, you will almost be able to use it.

(PS: At a certain point, there are some messy factory advertisements about how to make water writing cloth, and there are few practical ones, so the little brother wrote it according to what he thought, if there is a knowing little cutie, you can make a friendly proposal in the book review area, and then the little brother will change it, bow and thank you!) ）

For more than an hour, it was impossible for Lu Jiu to wait, so he simply continued to follow Fu Lanqing to learn to read.

Writing is too wasteful of paper, and Lu Jiu refuses.

Although not your own thing, it is indeed a shame to waste.

Today is also a good person with three straight views.

Qianqian: "...... "You can let go of the good guys, QAQ!"

Lu Jiu's way of recognizing words is very simple and rude, pick up a book and start reading, and even read it to Fu Lanqing with guessing, when there is a mistake, Fu Lanqing will point it out to Lu Jiu, and explain the meaning of this word to help Lu Jiu deepen his impression.

At this moment, Lu Jiu really admitted that Fu Lanqing was a god!

The word Xueba has defiled him on him, he knows astronomy and geography, knows everything, knows everything.

I really don't know how a sick seedling can understand so much.

More than an hour passed quickly, and Lu Jiu poured a lot of tea, and his throat was not very dry.

Lu Jiu took the fabric back to the room, then took out an unused pen, dipped it in the water, and then wrote on the cloth.

Miracles have happened again!

Really left the handwriting.

Fu Lanqing's eyes widened, very surprised.

But Lu Jiu frowned a little dissatisfied, and directly threw the piece of fabric aside.

tried several pieces in a row, but in the end, Lu Jiu only left two pieces of fabric.

Fu Lanqing observed it and found that the two pieces of cloth were not so badly smudged, as if they were writing on rice paper.

Lu Jiu was still pondering, and Fu Lanqing waited obediently.