"Brother Heng, you say, Sister Lizhi and Sister Yuzhang will be poisoned by the gas, but they brought back three coal stoves and some briquettes?" When Yang Heng finished explaining the gas poisoning, the little lady was worried about the two princesses.

"Don't worry, it's not time to use the coal stove yet, maybe they will use the coal stove to make those two dishes without salt, but only for a while, on such a hot day, it is impossible for them to light the stove in the room every day." Yang Heng comforted the little lady, but he himself was also a little secretly worried, according to some travel novels, Li Lizhi has such a disease as qi disease, and even Li Er's entire family has heredity, don't let the gas smoke, that is Yang Heng's sin.

…………

"What, Niangniang has a call, this guard brother, I don't know what Niangniang has to call our brother and sister." "Hehe, I'm sorry, I really don't know what to do, it's just that there is news from the palace that I want to invite the two of you." Yang Heng was a little nervous, was the two princesses really a little smoked by the gas, did the smoke of the gas disease happen in advance, worried, worried, perhaps, he was the only traverser who was cut down before he grew up, let's run, no, my father and mother are still there, and I finally lived a good life......

With apprehension all the way, Yang Heng and Xiao Niang came to the palace, and Xiao Niang was chattering and laughing all the way, all the way without stopping, this is the first time she came back after leaving Chang'an, and even thought about going to see which little friend, which best friend, you know, when Xiao Niang was in Chang'an, she was very popular, she not only followed Yang Heng, but also had a lot of girlfriends, but only two princesses of her girlfriends appeared in front of Yang Heng, None of the other girls had ever appeared in front of Yang Heng.

After entering the palace, Yang Heng was a little relieved, because he didn't see any sad atmosphere, you must know that these two princesses are Li Er's two favorite daughters, and naturally there is an unborn princess named Li Mingda who is also Li Er's favorite.

Since there is no sad atmosphere, then Yang Heng is safe, fortunately he didn't do anything excessive, it's ridiculous to think about it, when he talked about the gas matter earlier, he was so scared by himself.

"Niang Niang auspicious," after seeing the eldest grandson, Yang Heng was so excited that he actually said the words of the braided minions in later generations, but is this really the words of the braided minions, Yang Heng was also a little confused.

"Auspicious, auspicious, I said Yang Heng, you kid, why do you have something new every time I see you, what kind of greeting is this auspicious?" The eldest grandson was a little funny, it was obvious that Yang Heng was a little nervous, but what would make Yang Heng nervous, she naturally didn't know that Yang Heng was worried about the coal stove.

"Niangniang, how are you doing, my little lady misses you so much in the countryside." Xiaoniang is another way of greeting, but seeing that she is getting older and older, there can be several times this kind of greeting.

"Come on, little lady, I haven't seen you for a while, but I've grown up again, and I'm beautiful." The eldest grandson stepped forward and took the little lady's hand affectionately and looked up and down, maybe she thought in her heart, maybe the next time she could give birth to such a lively and lovely daughter, how good it would be, Lizhi, although Yuzhang is very cute, but they are always a little rigid and somewhat restrained, this is the result of heavenly education, in fact, anyone likes some harmonious farm life, but farm life is really like what these high-ranking people can imagine, although the eldest grandson suffered when he was young, but that kind of suffering is also the life that some farmers envy.

"Come, little lady, tell Uncle Niang, I heard that you made something burning in the countryside, what can you tell Uncle Niang." This, the temptation is coming, and the problem is also coming, Yang Heng also knows the reason why the eldest grandson called them here, Li Er is afraid that he will miss something good, so he naturally wants to know the Tao as soon as possible.

"Niangniang, let me tell you, the last time the two princesses went, there was no real successful test, so I didn't let the princess bring back specific news, and now it's finally a success, just right, Niangniang also wants to be a little girl, and I'll report this matter together."

What seventy-three eighty-four, Yang Heng directly reported again, "However, Niangniang, this is not very successful, first of all, this requires a lot of copper, if you use more copper, maybe the country will lack coins to use, and there is, now I use glutinous rice soup and mud, which increases a lot of costs, and it is also difficult to popularize, if it is not very cost-effective compared to the benefits of biogas, plus not all people can use it well, maybe this thing will become an ornament." "This is also the truth, if you don't know how to use it, it will really become a decoration, now there are a lot of such decorations around the author, the state gives a lot of money, but the people who can use it are not used, and the people who can't use it are built, and they are not used, it becomes a decoration, naturally, in Datang, maybe Li Er will add some decorations when he gives an order.

"So, what do you say? Listen to you, this is something that is good for all parties. Li Er suddenly walked out from the side, at this time, this matter was no longer something that the eldest grandson could solve.

"Your Majesty, this matter, I think it's better not to be impatient, although this biogas has a lot of benefits, but it also has to be used well, now I have some new ideas, maybe it can replace the glutinous rice soup and mud, if this idea is successful, it will greatly reduce the cost of making the pool, if there are really some wealthy families want to do it, I can personally instruct, to make some biogas digesters out, copper coins, maybe there will be a solution after a long time." Yang Heng won't say, copper mines, you can go to the sea to find it, that is, in that or where, what kind of person is this Yang Heng, there must be a road before the car reaches the mountain, and everyone's affairs will still be solved, it depends on how to solve it.

"Okay, I'm waiting for your solution, but you can give it to some wealthy ministers, or someone, it's not that we don't have enough copper coins, but that the copper coins are hidden in the hands of these people." Li Er naturally also knew that there were a lot of copper coins that had not been circulated in the world at this time, so it naturally seemed that there were not enough copper coins.