Solovyov in Tsarist Russia 1796.

Polina's health was deteriorating, so she stayed in Paris, where the medical conditions were better, and doctors in Paris were always more reliable than those in London.

Being able to see her children nearby also helps alleviate her condition.

After Octavia and Demid had four children, Demid still felt somewhat sorry for his wife. Although Octavia said that if conditions allowed, the two of them could continue, as she was in good health and there was no problem, unlike Davu's daughter who had walked through the gates of hell.

But Demid said they could wait and relax first, since the four children were already quite a handful.

The boy was alright, but Mrs. Recamier's two daughters would fight over the youngest baby every time they came, which was the complete opposite of their usual well-mannered image.

Especially the children born to Octavia, who are considered their nieces and nephews, are truly two noisy aunts.

"But Dad wrote a letter; he seems to have made some discovery. If it's poetry and music, that's fine, but if it's something mechanical, it's probably related to your friends."

Demid took the letter from Octavia. His father-in-law always wrote in neat and clear italic characters, which were very comfortable to read.

But there is also a terrifying handwriting style in Russian, which Demid had never been to St. Petersburg and therefore did not know.

Solovyov wrote many letters to his daughter, always feeling that he owed Octavia something and therefore always trying to make up for it.

Moreover, he also longed to see his grandchildren, but Paris and St. Petersburg were simply too far apart. Unlike the generals who returned to their estates, he still had official duties to fulfill, and he only visited his daughter's home twice on his return trips from overseas visits.

However, these mundane family matters are indeed very suitable for concealing Solovyov's true purpose.

Octavia's reading comprehension was perfect; she saw what her father mentioned later.

After reading the letter, Demid roughly understood the situation.

"It seems that Count Michel has discovered a useful new fuel with combustion characteristics similar to Greek fire, but it is a purified liquid, and he believes that there is an ideal model for combustion efficiency."

"Although Dad knows a lot, he doesn't have time to study it, so he wrote to me about it, probably asking your friends to refine the theory."

"That's right, it's a pity we don't have Lavoisier's brain, we can only rely on others."

Demid himself has already made some progress in physics, and he wants to join the French Academy of Sciences, just like his emperor uncle, but he also needs to make some theoretical breakthroughs.

You can't get in by relying solely on coding science; you need other research, even theoretical ones developed in collaboration with friends.

In this regard, it must be said that the Cano family are all engaged in scientific research, but they are also prone to getting involved in politics. That is, Napoleon II is currently on the throne, and his cousin Demid will not be able to rule in his own right for several years. Therefore, military and political power is in the hands of the Queen Mother, Prime Minister Talleyrand, Minister of War Soult, Commander-in-Chief of the Imperial Guard Ney, and Commander-in-Chief Davout, which has made the regime unusually stable.

Because of the Queen Mother's family's stance, there was an unprecedented level of tolerance in French politics. The Jacobins, who were usually quite volatile, were now surprisingly quiet. The power of the royal family, the Paulines, was weakened, and there was no retaliation.

This environment was actually much better than the era of Napoleon's military prowess. After all, there was no need to fight wars, farmers could have wives and children and warm beds, workers had jobs, capitalists had places to make money, and new nobles began to gradually replace the old nobles.

Only when the world of royalists within the church was damaged did the young emperor's great-uncle, who was a bishop, emerge. From the perspective of the Bonaparte family, Monsieur Talleyrand was the former abbot, and the current powerful figures generally disliked the church. Therefore, they simply returned the church to the bishops, and their influence was limited.

The land belonging to the church was therefore also allocated.

Of course, such a relaxed environment is beneficial to everyone, including scientists.

Demid was used to seeing child prodigies. Galois was only twelve years old, but he had already shown the same talent as Gauss at the same age. He himself was recognized as a genius by his uncle and father-in-law.

His old partner, Sadie Cano, the eldest son of the Cano family, is a genius in science and engineering. He recently resigned from his position in the General Staff and went to the Polytechnic Institute to do research.

Of course, he retained his rank as an engineer and the research stipend that Demid had applied for for him.

Sadie Cano's recent focus has been on thermodynamics, and he's completely absorbed in his work. Demid had even considered introducing him to a girlfriend, since he has three sisters-in-law and a younger sister, but Sadie wasn't interested in any of that.

Even the prettiest girl only slows down his research.

Demid could only laugh helplessly when he mentioned this. His friend was so engrossed in his research that he sometimes forgot to eat and sleep, completely oblivious to the outside world.

Fortunately, Paris is currently stable, and the Demids took a carriage to the École Polytechnique, where Sadie Cano was recently staying.

“Your Highness, you have come at just the right time. My brother’s research has made some progress, but he needs someone to help him refine it.”

What research findings were made?

"It's a thermodynamic cycle. Engineers always want to find the perfect heat engine, but they can't because their inventions aren't universally applicable."

"It's like in mathematics, using exhaustive search or incomplete induction based on a set of data, which consumes too much time."

"You must have made some progress by coming here."

“You know my father-in-law, Count Solovyov. He wrote from Russia, mentioning that a new type of fuel is being extracted in the Caucasus Mountains. He said the raw material is shallow petroleum in the Caucasus Mountains, and he expects to have finished products in the next year or two, first kerosene, then light fuel, and the residue can also be utilized. But what he wrote can only be used to inspire ideas, not as a solid theory.”

"That count has too much energy to spare for other things, so he has very few scientific achievements, but it should still be worthwhile to listen to his opinions."

After all, when Gauss was studying the normal distribution, Solovyov was not on the front lines fighting and had put forward some of his own ideas. Although he mainly used statistical methods, Gauss quickly improved his research according to his statistical methods.

Solovyov's main concern this time was fuel. In the latter part of his letter, he also mentioned that he believed there was a suitable fuel that could be used in a heat engine with a thermal cycle, in which the entropy could remain roughly constant. However, he also needed to summarize the rules for how this cycle should work.

Solovyov could actually conceive of the Carnot cycle, but he couldn't prove it; he merely applied the principle. Even time travelers aren't omniscient; those who are omniscient are likely to be burned at the stake.

This theory was originally developed by Sadie Cano. Solovyov wrote to him, which accelerated the research process, but it wasn't Eureka who did it.

It wasn't some bizarre story about Russian villagers sharing internal combustion engine technology; Solovyov's letter mainly focused on fuel and his ideas.

Sadi Kano also knew about Wallachia's oil resources, as well as the improvement of steam engine efficiency, and which type of heat engine should be used. He was also close to coming up with the cycle theory.

This process is divided into four stages to complete a thermodynamic cycle.

When Demid arrived at his studio, he saw Saadi sitting there, saying nothing.

"Saadi, will our visit at this time be of no disturbance to you?"

“I do hope to have a serious discussion with my friend, Demid. Your strengths are coding and optics. While you have good aptitude in thermodynamics, you're only at the level of an engineer.”

"Yes, I roughly know what you want to study. This is a letter from my father-in-law. He is looking for high-quality fuel and has proposed a possible cycle, but he doesn't have the energy to complete the paper. He only mentioned that the efficiency of steam engines has gone through two stages of evolution before reaching its current level."

"If the Earl were to be considered a historian in the field of engineering, he would be considered outstanding. He was very knowledgeable about those old steam engines in the archives."

"Yes, the letter mentioned these things, from the earliest steam-powered ball toys to old-fashioned steam engines, then to Watt's steam engine, and now to the new steam engines with safety valves, but the latest structure, if it could be researched..."

Solovyov did have experience organizing people to conduct collective research before, but it was mainly in the application of weapons. Regarding steam engines, he hired French engineers to help him improve the design of steamships. Now he believes that using fuel for four-stroke reciprocating cycle propulsion, or some other cycle method, to drive the machine may be more efficient than steam engines.

Efficiency is there for all to see, and advancements in materials and processes take time. Technological breakthroughs always occur earliest in countries that develop first.

Solovyov was not familiar with the British academic community, and his contacts with Europe were usually in France and the German Confederation, so he would naturally seek their help if he had any questions.

The rise of Russia's scientific community will take some time. In the past, having one Lomonsonov was already remarkable. In the future, as Russia increases its investment in education, many outstanding scholars will emerge, especially in mathematics, physics, and chemistry, which will be astonishing.

But now, Solovyov can only rely on French chickens to lay his own eggs.

That's what the big bad fox used to do, biologically speaking.

The same applies to science.

After seeing his letter, Sadie Carnot could only say that the count and he were of the same mind, but he simply did not have the means to put it into practice.

Solovyov indeed lacked the ability; his suggestion merely refined Carnot's theory. However, regarding the "ideal fuel," the efficiency of the steam engine was naturally inferior to that of the ideal heat engine, firstly the reciprocating steam engine, and later the internal combustion engine.

“But following this line of thought will still take time. I just hope that the Earl can bring over his ‘ideal fuel’ and improve the application of the ‘ideal heat engine’.”

Solovyov received replies from his son-in-law and Sadie Cano in 1823. The Dubinin brothers' distillation apparatus was able to recover kerosene. Although the components of the fuel oil were also extracted, they could not be used yet, so they could only be put into Molotov cocktails and distributed to the soldiers.

If the process can be further improved to fractionate various petroleum products in different sections, then qualified fuel oil will be available.

However, the quality of Russian oil is generally poor, which Solovyov could only deeply regret.

The best one is probably the light oil from the East Indies, which turned even the most basic boat into a leaky fire starter; it can be directly stuffed into the fuel tank.

The worst is the viscous stuff from Bolivar, but its advantage lies in its huge future production.

The quality of the oil produced in Russia can only be described as above average.

If we're going to develop internal combustion engines, the first finished product will probably be something like coal gas. As for fuel oil, we'll have to look at the finished products from petroleum fractionation.

To this end, Solovyov even wrote a letter to Countess Sofia, mentioning the achievements of the Dubinin brothers whom she had patronized, and expressing his hope to increase investment, offering to provide 10 rubles himself.

Now Solovyov spends 10 at a time, whereas back when he started making pencils and makeup brushes, he needed several children to chip in for him.

But of his young friends, he was the only one still alive in Russia.

One of the Dolgorukov brothers died of illness, and the other died in battle in Finland.

Madame Le Brun naturally returned to France. The lady was getting old and was preparing to retire from the art world. However, the children of her old Russian clients would still visit her in Paris, so she would sometimes still take commissions.

The "little fairy" was also in Paris. The products from those cosmetic factories back then were all lying in her luxury shops in Paris. When she turned forty and opened her own shop, she realized why Solovyov always mentioned that business was more profitable than the estate.

Then, apart from the estate she left to her daughters, she sold everything and even asked Madame de Récamier to invest in her, living the life of a wealthy woman in Paris. Her professional "fainting" became material for young Parisian novelists.

Well, this looks pretty good, but Bagration can't see that his wife is actually earning money on her own.

Solovyov recalled all of this and marveled at how quickly time had passed, and at the wild donkey that had galloped away.

He didn't have much to do at the moment, except for a letter from Louisa.

Because her health was deteriorating, the doctor suggested that she go to Italy for treatment, but she was unwilling to go to Italy and couldn't bear to leave her unmarried daughters. Instead, she hoped to go to a place in the south where she could recuperate.

Alexander even joined in the fun, but instead of choosing the palaces and estates Solovyov had planned in Yalta, they made other arrangements. (End of Chapter)