Just when Kong Yingda and the others were puzzled, the professor turned around and used a white pen to write down what he was going to explain on the blackboard.

Kong Yingda and the three of them watched in amazement as the professor wrote and drew on the blackboard.

It didn't take long for a passage to be written.

Kong Yingda asked suspiciously, "Lord Yuan, what is this professor using?" Why do you leave a font on a black wooden board? ”

Yuan Tiangang said: "This is chalk, which was invented by His Royal Highness King Liang entrusted by His Royal Highness King Jin. ”

Kong Yingda asked suspiciously: "Isn't this kind of teaching a waste of wood?" ”

Yuan Tiangang shook his head and said: "The Kong sacrificial wine is going to be divided, and the font written on this thing can be erased at any time, and there is no need to replace the wooden board again." ”

Kong Yingda let out an "oh" after hearing this, and then observed carefully.

I saw that the professor quickly filled the blackboard, and then picked up a board and erased it on the blackboard, and the font on it disappeared some.

The professor repeated the action several times, and soon the blackboard was back to its original state.

Kong Yingda was very interested in this.

He hurriedly opened his mouth and asked Yuan Tiangang, "Lord Yuan, is this thing convenient to make?" Can you make some for Guozijian? ”

Yuan Tiangang said with a smile: "Chalk is easy to say, this hospital can be open to supply, but this blackboard and eraser need to be Kong Saijiu to find the general as a prison for help." ”

Kong Yingda asked: "So the supervisor knows how to make it?" ”

Yuan Tiangang said: "It's not a secret, the blackboard of this hospital will be made by the prison. ”

Kong Yingda nodded and said, "This official will contact Lord Yan by himself." ”

Next, the group looked at two more classrooms in a row, and finally saw the arithmetic lesson in the fourth classroom.

The two arithmetic professors looked curiously at the blackboard, wanting to see how it differed from what they had learned.

At this glance, the two were completely dumbfounded.

Because they can't understand what is written on the blackboard.

Students in this era can be very different from previous lives.

Not only do they not have winter and summer vacations, but they only have two days off a month.

The only thing children do every day besides learning is exercise.

As a result, they are learning very quickly.

In just one year, I have already learned the knowledge of the junior high school part.

At this time, the teacher is teaching the knowledge of functions.

The teacher's mouth was talking about variables while drawing shapes on the blackboard.

The two professors of Guozijian couldn't see or hear outside.

The saddest thing is that they don't even recognize the letters and numbers written on the blackboard.

After working hard for a long time, the only thing they gained was to know a few Arabic numerals.

The rest can be said to be nothing.

At this time, the two of them completely believed what Yuan Tiangang said.

The arithmetic that people teach here is probably not the same thing as what they teach.

The two professors originally wanted to discuss their teaching experience with Yuan Tiangang.

But now this idea was suddenly dispelled.

The knowledge on both sides doesn't match, this is a fart!

The next visit made the three of them speechless throughout the whole process.

Because they soon saw the teaching scenarios and laboratory courses of physical chemistry.

Watching a group of teenage kids fiddling with various chemicals in the lab, the three of them suddenly felt like they were breaking down.

Kong Yingda soon left the academy with two professors.

The stimulus they received today was too great, and they needed to go back and take a good break.

After Yuan Tiangang sent Kong Yingda and the three of them away, he thought of going to the laboratory dedicated to Li Su's students.

Li's students are now science professors at the college.

When they don't have classes, they do their research in this dedicated laboratory.

Li Zhi left them with a lot of research topics.

Chief among them is the study of explosives.

The study doesn't seem to be going very well.

Because up to now, several research directions proposed by Li Zhi have not yet been able to see results.

Yuan Tiangang wanted to see if they needed help.

Just as he walked to the door and tried to push it in, the door was suddenly opened.

Yuan Tiangang raised his eyes and saw a person holding a small glass bottle in his hand and walking out cautiously.

He hurriedly dodged out of the way, and at the same time opened his mouth to ask.

At that moment, another person suddenly appeared behind the man and made a silent gesture to him.

Yuan Tiangang closed his mouth in confusion and turned his attention to their behavior.

The two cautiously walked towards the back door of the academy.

A large open space outside was the site that Li Zhi had left for them to carry out the blasting experiment.

Yuan Tiangang saw that he already had the answer here, thinking that one of the explosives had already been made.

Without saying a word, he followed the two of them until he walked a long distance before stopping.

Then the two men looked at each other.

Then the man with the vial gritted his teeth and threw it out.

This time it was thrown far away, but even so, the two of them still subconsciously made a dodge move.

A loud explosion was heard.

Yuan Tiangang's body shook violently, and then he watched in shock as dust and smoke rose up in front of him.

His ears were even more violently resounding with a loud bang.

For a moment, he wanted to scream.

The two professors ran to the bombing site as soon as the dust settled, and then carefully observed.

Yuan Tiangang also walked over cautiously and found that there was a huge pit with a diameter of more than half a zhang in front of him.

And the deepest part of the crater was more than a foot.

This made Yuan Tiangang's eyes widen suddenly.

You must know that the vial just now is very small, and Yuan Tiangang can be sure that the contents inside are definitely less than one or two.

Yet it is such a small thing that can cause such great damage.

The two professors looked at it carefully and burst out laughing.

After a long time, Yuan Tiangang asked suspiciously, "What kind of explosives are you made of?" Why is the temperament so fierce? ”

One of them smiled and said, "Lord Yuan, this thing has been named nitroglycerin by His Royal Highness the King of Jin, and it is the most unsafe type of explosive. ”

Yuan Tiangang asked suspiciously: "In that case, why do you have to spend so much effort to develop this thing?" ”

The man replied with a smile, "Although this item is not conducive to a large number of uses, His Royal Highness the King of Jin has mentioned another possible use. ”

Yuan Tiangang asked suspiciously: "I don't know what kind of use can make you take such a big risk to develop?" ”

The man said, "His Royal Highness the King of Jin wants to try to treat heart disease with this thing. ”

After hearing this, Yuan Tiangang immediately blurted out: "How is this possible? Wouldn't ordinary people take this thing and disappear in an instant? ”