Not long after Li Jiulang left, Master Xuanzang heard the news, and when he saw that Tang Xiu was unharmed, he lightly called the Buddha and said: "Amitabha, seeing that Tang Jushi can return safely, the poor monk is also relieved." ”

Tang Xiu replied: "Master Lao bothered, Xiao Ke didn't encounter any accidents, he just wandered outside for a while and came back late. ”

"The poor monk has never worried about the safety of Tang Jushi," Xuanzang expressed his meaning very bluntly, "Regardless of whether Tang Jushi encountered an accident or not, the poor monk believes that with Tang Jushi's dark strength beginner cultivation, there should not be many people in Chang'an City who can trap Tang Jushi." ”

"Master Xuanzang's discerning eyes!" was exposed by Xuanzang, and Tang Xiu no longer covered it up, so he simply admitted it calmly.

"The poor monk is most worried and anxious," Xuanzang continued: "I'm afraid that Tang Jushi will stay outside for too long and miss the Buddha site in the Big Wild Goose Pagoda." The things that Tang Jushi needed were all ready, and he also invited a few top craftsmen from the Ministry of Industry to come over, and now he is waiting for Tang Jushi to observe in person. ”

Tang Xiu's face was pale, this Master Xuanzang is really unpleasant, even if you really think so in your heart, there is no need to say it?

However, Xuanzang was able to get all those things together in such a short period of time, which really surprised Tang Xiu, even if the luminous beads were forgotten, the Tang royal family should have a lot of collections, and it might be relatively simple for Xuanzang to obtain the right beads.

But those convex lenses can not be polished well overnight, first of all, we must find a large enough transparent crystal, in fact, we have to rely on manual polishing little by little, the size should be consistent, the thickness should be moderate, and the surface must be smooth, the penetration should be good, according to Tang Xiu's estimate, just for polishing, it will take at least one to two months for the most skilled craftsman to polish a qualified lens.

But now that less than ten days have passed, Xuanzang actually said that he had gathered everything, which is inevitably not surprising.

Tang Xiu looked up at the sky, the sun was shining well today, and it was still noon, it was the best time to verify the lenses, so he happily agreed. In fact, he was also curious about the craftsmanship of the craftsmen of this era, and he also wanted to see how intense the legendary luminous bead could shine under the concentrated illumination of the convex lens.

"Actually, I don't have to go there myself, didn't I leave the drawings for the mage before?" Out of the courtyard gate, Tang Xiu asked Xuanzang casually: "According to the map, it shouldn't be difficult for those craftsmen, why does the master have to come and invite me?" ”

At the beginning, Tang Xiu didn't plan to stay here for long, so as early as the day before yesterday, he had already drawn the drawings in advance and handed them over to Xuanzang, and as long as they installed them step by step according to the requirements on the drawings, they could basically achieve the effect of making the luminous beads shine at night.

And this series of things that happened today, Tang Xiu already had a plan in his heart to leave Chang'an, if Xuanzang didn't come to him today, he would also go to Xuanzang tomorrow to say goodbye.

There are many rights and wrongs in Chang'an City, and he has only been in Chang'an for less than half a month before he has been remembered, which is really not a good sign, and it is better to leave early.

Faced with Tang Xiu's question, Xuanzang's answer was very simple: "Don't bother the two masters, since the layman is still in the temple, why bother so much?" ”

"Moreover, although those craftsmen polished those transparent spars according to the requirements of the laymen, they didn't know what the spars were used for and how they should be used, so before they officially installed those things on the top of the Big Wild Goose Pagoda, the poor monk wanted to let Tang Jushi try them first to see if there was anything wrong or something that needed to be improved."

Tang Xiu nodded suddenly.

Convex lenses were still a novelty to these ancients, and he did not say anything about the specific utility of convex lenses on his drawings, so it is no wonder that those people could not understand them.

According to Tang Xiu's design, the requirement for the convex lens is one meter in diameter, and the thickest place should reach about ten centimeters, and the light-gathering ability is absolutely super-first-class, but this also limits the super weight of the convex lens, how can such a large stone have to have a few tens of kilograms, and ordinary people will never think of carrying him to shine under the sun, so naturally they can't find the magical function of the convex lens.

While thinking about it, the two of them had arrived at the innermost place of the temple.

In a courtyard that seemed very empty, Tang Xiu saw the craftsmen of the Ministry of Engineering that Xuanzang said and a giant convex lens they had prepared.

There were three craftsmen, each of whom was in his forties, with thick arms and bright eyes, and he was in the prime of life.

There is only one lens, placed on a wooden box, and a thick layer of silk brocade is padded underneath, for fear that the smooth lenses will be worn.

"At present, only this one piece has been polished," Seeing Tang Xiu look at the lens and look at himself again, with a trace of doubt on his face, Xuanzang explained unhurriedly: "The other pieces are still working day and night, and I believe that it will not take half a month to make them all." ”

"If you have a piece, you can barely try it."

Tang Xiu nodded lightly, knowing that Xuanzang was a little uneasy, and wanted to see in advance what the effect of the luminous bead glowing at night was, if not, it was estimated that there would be no more overtime in the future.

Tang Xiu stepped forward and touched the lenses polished by these craftsmen, they were really smooth as jade, transparent as wash, and the structure was symmetrical, the curve was natural and smooth, this craftsmanship, this workmanship, it was really amazing.

Tang Xiu raised his hand and moved, at least a hundred catties, it is estimated that it will be a little difficult to erect it to the top of the tower at that time, but those are all things in the future, and it has nothing to do with him. What Tang Xiu has to do now is to make use of this lens and show Master Xuanzang what a miracle is.

Hold the lenses high, and then measure the focal length of the mirror directly to the sun, about one meter five or six, fortunately, it is not as far as expected, and when these lenses are placed on the top of the tower in the future, they will not be redone or extended out of the tower because of the problem of too far focus.

"Just now, I wasn't dazzled, was I? Is there a particularly bright spot of light on the ground? ”

"I also saw it, although it was only for a moment, but it was true, it looked so bright in the daytime, wouldn't it be even more dazzling if it was placed at night?"

"yes, yes, I didn't expect this thing to be used like this......"

The three craftsmen were full of surprise, even Xuanzang's heart was hot, they didn't expect that the transparent crystal that Tang Xiu asked them to make was so magical.

However, Xuanzang did not think that this crystal could also shine at night like these craftsmen, and he obviously noticed that the reason why there were light spots under the crystal was entirely with the help of the sun's rays.

Now Xuanzang has begun to understand the specific function of this magic crystal, it turns out that it can gather sunlight and concentrate them all in one point.

Hearing the discussion of these craftsmen, Tang Xiu smiled slightly, gently put down the lens, and asked the little novice next to him to fetch a piece of dry firewood, and then under the gaze of everyone, Tang Xiu bent down and put the firewood on the bluestone ground next to him, and then picked up the lens he had just put down, and hung it in the air against the sun again, so that the extremely bright point of light gathered by the convex lens shone motionlessly on the firewood on the ground.

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