Yuan Tiangang and Li Chunfeng moved to the chemistry laboratory to do experiments, Zhang Nan was not as dedicated as the two of them, after bringing the two over, Zhang Nan briefly told them about the use of some equipment and the precautions of some chemicals, Zhang Nan went directly to Mozu.

Walking to the office of the Tiangong Department, Zhang Nan suddenly found a familiar figure.

"That, are you Bai'er, or Qing'er." Zhang Nan really couldn't tell the two sisters apart, because the two sisters looked too similar, more similar than any twin Zhang Nan had ever seen.

The woman rolled her eyes at Zhang Nan, and Zhang Nan immediately knew whether this was her sister or her sister.

"Okay, needless to say, I know you're a sister. By the way, is Mozu here? Zhang Nan asked.

"Mozu hasn't come back yet, if you want to see Mozu, just wait." After Bai'er finished speaking, he made a gesture to leave. Zhang Nan immediately stopped Bai'er.

"No, how can I say that I also helped you improve your steam car, you are too outstanding, do you think that the steam car you made is too bad, ashamed?" Zhang Nan asked with a grin.

In fact, these two sisters are very good girls, Qing'er Zhang Nan doesn't know very well, but Bai'er is definitely a hegemonic figure in later generations, just by looking at the prototype of the steam engine, you can think of designing this steam car, although it is not perfect, but the imagination is definitely in line with Zhang Nan's standards, especially Zhang Nan also pointed to this Bai'er and then designed steam trains and steam ships, this relationship must be good.

Hearing Zhang Nan say this, Bai'er blushed rarely, and said: "You are ashamed, there are indeed some problems with the steam car I built, and there is nothing wrong with you changing it, this will always work." ”

"Eh, it's good that young people have the courage to admit their mistakes." Zhang Nan said with a smile.

"You?" Bai Er glanced at Zhang Nan strangely.

"You're not as old as me, are you, and you still call me young?" Bai'er said.

"Don't worry about these details, by the way, that steam car is actually still problematic, and you still have to continue to improve." Zhang Nan suddenly remembered the hot seat that burned his butt in the morning and said.

"Still have questions? What's the problem? Bai'er looked strange.

"Don't you think the safety factor of this steam car you built is too low? Especially the steam part, there is no protection at all, which is a big safety hazard. Zhang Nan said.

After listening to Zhang Nan's words, Bai'er showed a thoughtful look.

"But if you want to move the steam part out of the seat, wouldn't you have to enlarge the car again, so that the car will not get bigger and bigger? If it's so big, can a little steam equipment pull it? Bai'er asked.

"If you can't pull it, you can change to a bigger steam equipment, anyway, it's bigger, the power is enough, isn't there more things to pull? Besides, this Datang land is vast and sparsely populated, can't it put a large steam car? Zhang Nan guided Bai'er step by step to the road of the steam train.

"Well, you're right, I'm going down to think about it, you can wait for Mozu here." After Bai'er finished speaking, he was about to leave.

Zhang Nan saw it and stopped Bai'er again.

"Don't worry, I haven't finished saying this yet, why are you in a hurry." Zhang Nan smiled.

"What, do you have anything else?" Bai'er glanced at Zhang Nan vigilantly.

"Didn't you say last time that you had bad eyes, but now you are also a member of the Tiangong Department, and I, as your top boss, can't sit idly by." Zhang Nan said.

"You're still going to heal?" Bai Er's face was strange, she had never heard that this guy in front of her still had the attribute of curing diseases.

"That's natural, have you been vaccinated with cowpox?" Zhang Nan suddenly asked without a head.

"This, naturally, is vaccinated, although the last smallpox outbreak did not affect our Momen, but the people of Chang'an were vaccinated with cowpox, and we also went to be stabbed." Bai'er said.

"That cowpox was invented by me, how about it, now I believe I will cure the disease." Zhang Nan looked proud, and he did not feel the slightest sense of shame about stealing other people's achievements at will.

"You? Even if you made it, it doesn't mean it's useful, and I had a fever all night after I was stabbed. Bai Er's face was suspicious, obviously not at ease with Zhang Nan's medical skills.

Zhang Nan was speechless after hearing this, although he was not very sure whether this kind of earthwork was useful, but it was definitely not a knife in vain, hearing that Bai Er doubted his medical skills, Zhang Nan said: "Then I can cure your eyes now, believe it or not, if you don't believe it, forget it, this kind and kind treatment for your eyes, you are still doubting and doubting here." ”

When Bai'er heard Zhang Nan say this, she also knew that Zhang Nan had good intentions, so she changed her words and said, "Then how are you going to heal my eyes?" Do you want to drink decoction? ”

"No, the superficial thing like decoction is not a famous doctor like me, I usually use methods that produce immediate results. By the way, let me ask you first, do you only have blurry understanding with these eyes, or is it blurry with ghosting? ”

Myopia and astigmatism are still different, if it is myopia, Zhang Nan can directly change out myopia glasses of different degrees from the system to wear it for Bai'er, but if it is myopia and astigmatism, it will be much more troublesome, after all, Zhang Nan is not a doctor, and Zhang Nan can not tell how many degrees of myopia and how many degrees of astigmatism are Zhang Nan.

"It's just a blurry vision, no ghosting." Bai Er's eyes widened, and she looked carefully into the distance and said.

"That'll be easy, you wait." After Zhang Nan finished speaking, he changed out glasses ranging from 300 to 700 degrees from the system, as for the glasses frames, Zhang Nan chose the gold wire frames, after all, this looks a little more atmospheric, Zhang Nan is a little worried that the aesthetic Baier of later generations will not be able to accept it.

Faced with the pile of glasses that suddenly appeared in front of her, Bai Er picked up a pair of glasses very strangely and said, "What is this?" ”

Zhang Nan said: "This is called glasses, which is specially designed to deal with your disease of not seeing things clearly, you wear this on your eyes to see, choose the most comfortable, see things most clearly." ”

After listening to Zhang Nan's words, Bai'er began to try on glasses in turn, and in the end, Bai'er chose the pair of 500-degree myopia glasses, and after wearing them on her eyes, Bai'er first said "Huh", and then said to Zhang Nan with a surprised face: "This one is the clearest, it's really magical." ”

Zhang Nan looked at the first Tang glasses lady created by himself in front of him, and said with a smile: "That's natural, to tell you that what I pursue is immediate, there is absolutely no problem, since you look comfortable, then wear this one." ”