In the current social form, the most important timekeeping tools of Datang are still watches, sundials and missing engravings.

This watch is the oldest kind of timekeeper in China, in the ancient classic book "Zhou Li" there is a record of Tugui, in fact, its timing principle is also simple, is to use the length of the sun's projection to judge the time.

Sundials, on the other hand, are timed by observing the shadow of the sun, and the current hour or tick has been determined mainly according to the position of the shadow.

Compared with the previous two, both the watch and the sundial use the shadow of the sun to calculate the time, and once it rains or darkens the night, it immediately loses its effectiveness, so the missing moment comes into being.

Leakage, refers to a leaky pot; Engraved refers to the engraved arrow; The arrow is a ruler marked with a time scale, and the leakage is to hold water in a pot, and the time is calculated by observing the data displayed on the arrow engraved in the pot by using the principle of water balance dripping.

As a timepiece, the use of missing engravings is far more common than that of watches and sundials.

Of course, there are several more common timekeeping tools, such as incense seals, sand clocks, oil lamp clocks, candle clocks, and so on.

Among them, the most common, simply used to calculate the hour, is the chronograph incense, that is, the incense seal.

Therefore, the most important thing for such a small and delicate thing is to be able to carry it with you and watch the time anytime and anywhere, which is really incredible!

"I said, Brother Huang, don't underestimate this thing!" When Li Yuanba saw Li Shimin and Empress Changsun, they didn't believe that this small thing could replace the incense seal, so he explained:

"This thing is made from a spring. Brother Huang, you have all seen the spring, which can tighten and store energy, and can slowly release the energy, and it is this energy that can push the running mechanism and hands in the watch to achieve the function of displaying the time. ”

"A small spring, with so much energy?" Li Shimin still couldn't believe it.

"Brother Huang. The principle of operation of this watch is in fact to use a vibration system with a constant cycle and continuous vibration as standard...... Hey, I'm telling you this, you don't understand it! Otherwise, you have someone look at the time now, and then come back later. Then compare it with this watch to see if it can tell the time! ”

If you talk to someone who knows the principle of a watch, you can naturally understand it, but if you talk to someone who doesn't understand anything, it's completely like playing the piano to a cow. So Li Yuanba simply gave up, and then chose a relatively much simpler method.

It was not practical for Li Yuanba to say, Li Shimin also thought of this method, so he called Liu Sanshui in, specially lit a stick of incense, and put a leak on it.

Now that Li Shimin's mind is on the watch, he naturally left behind the matter of wanting to abdicate to Li Chengqian, and just stared at the watch at all. I'm afraid I'll miss something.

Seeing that Li Shimin unexpectedly revealed such a child's heart, Empress Eldest Sun and Li Yuanba couldn't help but become helpless.

"Brother Huang, Brother Huang...... You haven't said why you called me back. Could it be that there is something big about it? "Li Yuanba won't be used to Li Shimin, if you don't talk to me, I'll talk to you, right?

"Come back once, you kid. It's so easy that I didn't come back empty-handed, so why don't you take a good look? We'll talk about it later! ”

Li Shimin threw this sentence to Li Yuanba without raising his head, but there was a grievance in his words. But there was no such meaning in the tone.

"I didn't mean that." This is a lying gun, Li Yuanba shrugged his shoulders rather innocently, and continued: "Second sister-in-law, why don't you take a look at another gift box?" ”

"Is that a watch too?" Empress Eldest Sun also had a look of curiosity written on her face, so she reached out and opened another small box from the table.

"It's so beautiful!"

Compared with Li Shimin's pure gold watch, although the value of the eldest grandson queen is much worse, but in terms of appearance, it is much more beautiful.

The watch that Li Yuanba gave to Empress Changsun is made of white gold, and the scale numbers on it are inlaid with sapphires, and even the three hands are extremely beautiful and look very beautiful.

Li Yuanba laughed and said: "Second sister-in-law, the two watches you and the second brother have different meanings, they are the first men's watches and women's watches in our Datang territory, and only they can be worthy of your identity!" ”

"Oh? Shouldn't we feel honored? Hearing this, Li Shimin finally raised his head, and looked at Li Yuanba with a smile on his face.

The expression on Li Yuanba's face was stunned, and then he retorted: "Brother Huang, this is not what I said, you said it yourself!" ”

Li Shimin couldn't help but shake his head and said, "You kid, you still don't suffer so much!" ”

"Brother Huang, the two of us are each other!" Li Yuanba blinked his eyes and continued: "Okay, Brother Huang, the watch has been given to you, and I will ask my subordinates to send a few large vertical clocks over when I go back, and then you will study it slowly!" ”

"Okay!" After Li Yuanba's trouble, Li Shimin's excitement also passed, nodded and continued: "How long are you going to stay this time?" ”

Li Yuanba shrugged his shoulders and said, "How do I know? It depends on why the imperial brother called me back, if it's just some idle things, maybe I'll go back in two days! ”

"What's so good about the land that sets the heavens, you kid has been there for seven or eight years, and you can wait for flowers?"

Li Shimin glared at Li Yuanba angrily and said, "According to my meaning, you won't go back this time, and in the next time, you won't have time to go back to the land of Dingtian!" ”

"Huh? But why, is it possible that there is some place to rebel? ”

Li Yuanba was greatly surprised, for so many years, except for a rebellion in the small Japanese governor's mansion under the rule of the Nanyang Metropolitan Protectorate, and it was bloodily suppressed by the Tang Dynasty, such a thing has never happened in the vast land of the Tang Dynasty.

Li Shimin shook his head and said in a deep voice: "I want to abdicate!" ”

"Well, you want to retreat ......" Li Yuanba nodded subconsciously, and suddenly said loudly: "What are you talking about?" ”

"What are you doing so loudly? Your ears are going to be deafened by you! Li Shimin glared at Li Yuanba and said, "I said that I want to abdicate!" ”

Li Yuanba reached out and touched Li Shimin's forehead, muttering: "If you don't have a fever, why are you talking nonsense?" ”

"You go to the side of me!" Li Shimin angrily pulled Li Yuanba's hand aside and said, "I'm telling you seriously, don't give me a disturbance!" (To be continued.) )