"Got it! Hahahaha...... Lu Yuanzhi suddenly laughed, and said without thinking: "As long as the tin is slightly hot, it will melt, Shi will always burn the fire in the cabin, melt the tin, and pour it into the river through the dòng!" ”

Oh "I see! Everyone nodded their heads in a state of sudden realization.

Qin Lin laughed secretly, of course, what the fat man said also has some truth, the melting point of sterling silver is more than 960 degrees Celsius, and the melting point of tin is only more than 230 degrees, and the oil is heated to seven or eight percent at home, and there is this temperature, "So I was able to use a pot to "fry" the tin out of the dry sand mud.

Compared with silver, which has a high melting point, tin can be melted with only a little heat, and it is indeed easy to be discharged from the dòng."

Zhang Zixuan was the fastest reaction among the crowd, and immediately questioned: "This seems to be a bit unreasonable, it is true that the tin will melt as long as it is slightly heated, and it can be discharged from the dòng, but there is no trace of smoke and fire in the secret cabin, let's not care where the wood and coal come from, just say that they are burning fire in the secret cabin with only two xiǎo ventilation windows, and they are not afraid of burning themselves to death?" ”

The fat man grabbed his hair with great difficulty, and suddenly thought of what he had learned through the secret visit, and explained like a cannon: "I see! When I got up at night, I heard the officers and soldiers cough when they heard someone in the secret cabin: "It's smoked by smoke and fire!" The fuel used to heat the tin ingots was actually the liquor that Cui Sicang secretly transported to the cabin, and the old army saw the fish leaping over the dragon, because the molten tin was poured into the bottom of the river, and the fish jumped out of the water in shock! ”

Lu Fatzi only felt that he was analyzing the slightest detail, and laughed proudly: "Hahaha, it turns out that I am so smart...... Brother Qin, I didn't say anything wrong this time, right? ”

Ahem, Qin Lin smiled and touched the fat man's head, "Child, you can tell the wrong inference as the truth, you are bright!" Think about it carefully, how big a wine gourd is needed to burn and melt the entire 500,000 taels of tin ingots, and these melted tin, as soon as they enter the river, form a lump again, how can they not be salvaged and dissolved in the silt? ”

The fat man shrunk his neck, "Hehe, he laughed dryly, knowing that he was reasoning in the wrong direction."

"Tin plague" Brother Qin, it must be a tin plague, right? Zhang Zixuan's radiant eyes looked at Qin Lin, I don't know if it was blown by the north wind, or because of the excitement after finding the "answer" case, the beautiful goose egg face was flushed.

Qin Lin nodded, this is the correct "Answer" case, "The disappearance of the tin ingot in the cabin is not due to high temperature heating", but it is closely related to the rare cold in Yangzhou recently.

There are three allotropic forms of tin: white tin, gray tin, and brittle tin. Tin can have different crystallization states in different environments. Under the conditions of room temperature and higher than room temperature, the most stable form is white tin "White tin is a malleable metal" is often used by people to make tinware, wine pots, tea cans or something, Tang Seng's nine-ring tin rod is also this thing.

When the temperature drops to minus 13 degrees Celsius, the crystalline lattice of tin rearranges and the gaps between atoms increase" to form a new crystalline form, grey tin.

The internal stress that occurs at the contact between the different crystalline lattices of the gray tin causes it to break into powder.

The good end of the silver-white sè tin ware loses its luster and turns into a dark ash sè at low temperatures, and this tin "plague" will also be transmitted to others, and the "healthy" tin ware "a piece of tin ingot turns into ash powder" and scatters the ash powder on the tin ingots that have not yet been transformed" Soon all turn into ash powder, as if the epidemic is contagious, and people observe this phenomenon, which is called tin plague.

Tin plague is often seen in the cold areas of the north, but Yangzhou is warm, and people rarely see it, so no one thinks about it, how do you know that the result is so unexpected?

(Cat's note: The weather in Yangzhou is mild, but there is also a low temperature record of minus 20 degrees Celsius in 1918, which is "colder than minus 13 degrees Celsius when tin plague occurred")

The southerners present still didn't quite understand, "Those who have lived in the cold areas of the north suddenly understood, and Huang Gonggong sighed and praised: "That's true, our family was in the imperial supervisor in the early years, and saw that the tin in the Jingshi Palace had to add copper and lead when casting, and I don't understand why this is so, I think it must be to avoid the tin plague in winter with pure tin!" ”

Zhang Zixuan was still puzzled, she expected that Qin Lin must know the reason, so she only asked him: "With the weather in Yangzhou, the tin plague will not happen too quickly, how can it turn all 500,000 taels of silver into ash powder overnight?" ”

Qin Lin smiled but didn't answer, and asked Niu Dali to use wooden chopsticks to hold the tin that had just been fried, and stand in the wind. "Under the sub" also told Lu Fatzi to dissolve the red salt in the liquor and pour it on the tin block. ,

After a while, I saw that the tin gradually turned gray, lost its metallic luster, and suddenly became shattered, and the ox could not hold it vigorously, and fell to the ground into a pile of ash powder.

Only then did everyone realize that "it turns out that the mixture of red salt and spirits" can make the tin plague occur faster than usual!

Qin Lin smiled, the mixture of red salt and spirits "is the catalyst for the tin plague!"

Now the temperature is not as low as minus thirteen degrees Celsius when the tin plague occurs, but the volatilization of the wine jīng will take away the heat and reduce the temperature of the object below the air temperature."

Back to the night when "Caoyin" disappeared, the temperature was extremely low, and the conditions for the occurrence of the tin plague were reached, Shi took his own soldiers to pour the catalyst of wine jīng mixed with red salt on the tin ingots, and then withdrew the ash powder turned into the tin ingots into each box, so that without much effort, all the tin ingots turned into ash powder, which could be easily discharged from the dòng!

In this way, "all the strange phenomena have a perfect explanation, and the cough of someone in the cabin is due to the inhalation of ash powder in the heart: and the fish leaping dragon mén, the tin powder is discharged into the river, and the river water is polluted, and the gills of the fish are blocked by the powder, and they jump out of the water in pain!"

Why have no abnormalities been found in previous salvage attempts?

If it was a tin ingot or a silver ingot, it would have been scooped up a long time ago, but the tin ingots turned into a black ash powder, mixed with the silt at the bottom of the canal, "Who can see it?" It's not that Qin Lin found the reason through reasoning and deliberately fished out the silt to fry and refine, or in another five hundred years, people won't find out that there is tin powder at the bottom of the river!

The White Lotus Sect's case was almost seamless, but as Qin Lin said, there has never been a perfect crime in this world, and the only flaw they left behind was hidden in the silt at the bottom of the river: the density of gray tin is 5.75 grams per cubic centimeter, which is more than five times that of the river, so the tin powder will not be washed away after being discharged into the water, but will be deposited in the silt at the bottom of the river