After Sima Lang returned to the inn, while calming down his embarrassment, he shifted his energy and began to think about what he had seen and heard today.

"The treacherous is like loyalty, and the big hypocrisy is like the truth!" This is Sima Lang's current evaluation of Bai Tu.

What did he eat in the Che Cavalry General's Mansion before?

Fresh sea fish, vegetables, peaches and plums......

Is wine and meat considered a luxury? This may be true for the common people, but for the nobles of the great clans, it is obvious that wine and meat are nothing.

Fresh sea fish means ice that has been preserved by countless people, tree fruits that are not in season, and it means that it is necessary to build a fire chamber that costs people and money.

In the Han Dynasty, there was already a situation of out-of-season planting, but it was difficult for ordinary princes and nobles to enjoy, and even the emperor felt that it was too wasteful, and in the time of Emperor Han An, it was forbidden to use out-of-season vegetables in the imperial dining room - the investment of tens of millions of dollars a year, even the emperor was uneasy.

However, before in Baitu Mansion, Sima Lang recalled those fresh vegetables......

Not only fresh, but also in excellent condition, not to mention the off-season of vegetables and fruits in late spring...... Usually, Sima Lang rarely sees vegetables in such good condition.

If it was when the Han family could still cover it before, these vegetables and fruits would be placed in Luoyang, and I am afraid that they would be able to sell for gold!

Not to mention, the fine brocades worn by the waiters, and the cups of the feast were exquisite treasures.

Now that the world is in turmoil, the former princes of Gon are now a lot more diligent and thrifty in Xudu, and Bai Tu ...... Gee.

Sima Lang even wants to cry out for Wang Mang now - compared to Wang Mang, Bai Tu is really deceiving the world and stealing his name, and even ...... didn't put any effort into "bullying" at all, didn't even pretend to be a look, and was so successful in "stealing"?

Of course, in fact, Bai Tu didn't feel that when he was "treacherous".

After all, ice cubes or something, just the most basic, similar to saltpeter ice - the Tang Dynasty already had this technology, the use of saltpeter, the main component of potassium nitrate, dissolved in water when heat-absorbing characteristics, large basins in the nitrate, small basins in the frozen ice, only after the small basin of ice to use, the large basin of ice water re-dried saltpeter, can be used repeatedly.

It's just that in the Tang Dynasty, this technology was rarely used in the people, after all, saltpeter was the main ingredient of gunpowder, so as a dangerous good, it was very restricted in circulation.

And...... Even in the modern era, Huaxia is also a country where potash ore is scarce, and the total amount is scarce, and the source of potash saltpeter, that is, fire nitrate, is also very limited in ancient times.

However, it is not a big problem for Baitu, because the potassium in the sea can be said to be almost "endless", and the use of natural zeolite can "displace" potassium from the bitter brine left by the dried salt - clinoptilolite is rich in reserves in China, especially in the Jiangdong area.

Baitu also did not specifically mine saltpeter, but only used Pangtona's "potassium chloride", which is different from potassium nitrate, the main component of saltpeter, but the endothermic effect is similar.

The reason why potassium is extracted is not specifically to make ice for white charts, but to be used as fertilizer......

Potash is one of the most important types of fertilizers!

It can increase the protein content of grains, increase the vitamin C of fruits and vegetables, improve the size, color and shelf resistance of fruits and vegetables.

Although the future generations of fertilizer-free, pure green crops are very respected, but we have to admit that the emergence of chemical fertilizer is definitely a great progress of civilization, if there is no fertilizer to human development dividends, it will not make the productivity so high that people can dislike fertilizer crops......

At the end of the Eastern Han Dynasty, naturally no one disliked chemical fertilizers, just like Sima Lang...... After eating green food all my life, I tasted the out-of-season fertilizer vegetables and fruits for the first time today, and I was so "really fragrant" that I slandered Bai Tu in my heart, thinking that this was a manifestation of "arrogance and luxury".

Of course, the production and use of chemical fertilizers are still in a very early stage, and Pangtong is still in continuous debugging, and there is still a distance from civilian use.

Now it is mainly with glass greenhouses, as an important auxiliary means of breeding - in the short term, the focus of improving the output of agricultural products is to cultivate excellent varieties, and the popularization of chemical fertilizers will have to wait a little longer.

As for the glass greenhouse......

It is indeed a bit of a luxury, relying on a few government-run glass factories, it will certainly not be popularized to the people, and now it is only used for breeding, and in terms of off-season planting, Pang Tong is still researching a cheap alternative to mulch.

This year, the first batch of breeding products has entered the natural environment for cultivation, and if successful, it will play a huge leading role in the future development of agriculture!

The development of science and technology has made Bai Tu very confident in the future great cause.

Only now, Bai Tu has learned bad news...... Or rather, the bad news is finally confirmed.

"Didn't you find it?" Bai Tu looked at the paperwork in his hand and couldn't help muttering to himself, while rubbing the corners of his eyes with some distress.

"Didn't find anything? The kind of stone that can bake fire, you say? It's just folklore, don't pay too much attention to it. Seeing this, Lu Lingqi explained on the side.

That's right, just last month, when Bai Tu decided to take advantage of the gradual recovery of agricultural production today and the pressure of disaster relief to improve a wave of productivity, he found a fatal problem - the world of Chenghime...... There is no oil and coal.

It is said that in the "Geographical Chronicles" of the Han Dynasty, there are already records of "Gaonu County has water combustible water" and "Yuzhang produces stones, combustible for salary", it stands to reason that the former should be oil, and the latter is coal.

A few days ago, Bai Tu decided to mine a wave of coal as a highly efficient fuel, as for the steam engine...... It's not that hard in principle.

However, when Bai Tu told Lu Kang and the others about this, Lu Kang and the others all looked at Bai Tu with a strange face, and Yu Xuan, who had just returned from Poyang County, shouted directly, telling Bai Tu not to believe the nonsense of the folk monks.

That's right, what "Yuzhang comes out of the stone, can be burned for salary", they have never heard of it, the stone that can be burned...... No matter how this sounds, it sounds like the liar Fang Shi said!

At first, Bai Tu thought that it was because of the problem of popularity, so everyone did not know about coal, and gave the example of "Geographical Chronicles", and the result was ......

Someone was sent to fetch the "Geographical Chronicles" from the study and found ...... There is no such sentence!

Bai Tu clearly remembers that there is this sentence on his hard drive.

When he first found out about this, Bai Tu even wondered if there was an evil god hiding around him, and if he wanted to learn how to act?

For a long time, the overlap between the world of Chengji and the world before Bai Tu crossed over made Bai Tu a little careless.

It is natural to think that you can find coal......

However, the details of the Geography are different, and Bai Tu is somewhat aware that something is wrong - after all, they are not the same world, and even if they really don't, it seems that there is nothing strange about it.

So under the "dying struggle", Bai Tu specially organized a wave of survey teams, although Bai Tu's behavior was inexplicable, and for no reason he wanted to find a stone that could be burned, or even a black spring that could be burned, no matter how he looked at it, he was fooled and lame!

Fortunately, the other aspects of the white map are still relatively normal, and the so-called survey is only a team of more than 100 people, which is not a lot of labor and money, so except for the upright Yu Translation, everyone didn't care too much.

Now what Bai Tu has in his hand is the report document of the survey team, which has completely confirmed this bad news - Yuzhang, there is no coal.

Even when he had just learned about the difference between the versions of the "Geographical Chronicle", Bai Tu went back and looked at the record of oil in the Chengji version, and sure enough, it was ...... There are no records of fierce fire oil and water, so it can be basically speculated that oil does not exist!

Regarding Bai Tu's depression, Lu Lingqi felt a little like coaxing a child.

After all, in Lu Lingqi's opinion, it is naïve enough to believe in any "stone that can be burned" for no reason, and she is still depressed because she can't find it...... What is this not a little child?

"Obviously there are others, but oil and coal...... Wait, are there no fossils? Bai Tu was a little puzzled.

"Huh? What fossils? Wangfu Stone? Lu Lingqi wondered.

"Ahem, nothing ......"

"Don't feel bad! Isn't it okay for us to burn charcoal? Lu Lingqi coaxed child-like comfort.

Bai Tu rolled his eyes and said helplessly: "It's not a matter of burning charcoal, there is no coal...... Forget it, I'm fine. "Bai Tu also understands that it is difficult to explain to people who don't know what coal and oil are.

It is a trivial matter that there is no fierce fire oil that can be used for fire attack in the war, but there is no oil as the "blood of industry" in industry, which greatly hits the development prospects of Baitu's technology tree.

It's not just about fuel, from artificial plastics to asphalt, lubricants...... Countless industrial products are based on petroleum.

It can be said that without oil, there would be no modern industrial civilization.

However, in the world of Castle Hime, it is likely that there is no oil at present, and even ...... Not even coal!

If the absence of oil restricts the upper limit of Baitu's tech tree, then the absence of coal directly frustrates Baitu's immediate development plan - without coal, charcoal can only be used as the main fuel.

Well, during World War II, when a certain mustache was in internal and external difficulties, because of the lack of resources, he also had charcoal-burning tanks......

If you just burn charcoal, burning the entire wood of the Great Khing'an Mountains into charcoal is far from enough to develop modern industry - that is, in terms of resources, you cannot copy the modern science and technology tree.

"Or ...... Is it okay to let the woodcutter chop more firewood every day? Lu Lingqi didn't understand what Bai Tu was worried about.

"No, don't bother the woodcutter...... Wait a minute! Woodcutter? Bai Tu suddenly thought of using a woodcutter to extract Artemisia annua potion - of course, the woodcutter here is not an ordinary woodcutter, but a nameless woodcutter who is responsible for the firewood supply under the Steward Wang of the Internal Affairs Department of the Che Cavalry General.

Although there are no fossil resources, there are ...... It seems that there is another "resource"?

Maybe if you want to find a different way, you should focus on this aspect?

"You're so smart!" Bai Tu looked at Lu Lingqi and said seriously.

When Lu Lingqi heard this, she also said seriously: "Are you too stupid?" After saying that, he laughed first.

From beginning to end, Lu Lingqi felt that Bai Tu was innocent and cute this time......