Mary's Nineteenth Century

An ancient castle hanging on the sea needs enough storage space.

The size of the floor area of ​​the building on the ground is the size of the basement area.

The owner of Page Island does not like the dark and humid environment, and only uses a small part of the space for storage, while four-fifths of the space are left unused.

Idle does not mean empty, but the items of the previous owner of the castle, such as furniture, various sundries, daily necessities and equipment, etc. have been piled up.

"How can there be a secret passage here? I have never built a secret passage, and it was not on the structure diagram when the Marquis built the castle."

Page came to the location where the blood was found. There were obvious traces of moving heavy objects. A cabinet with a broken leg was originally placed there.

Right now, the cabinet was moved one meter away, and the carpet was lifted, revealing an iron cover with a diameter of about 0.7 meters.

There are a few strands of clothes fibers on the edge of the iron cover, stained with blood, indicating that someone wearing blood clothes has just entered the dark passage below.

The housekeeper remembered the maintenance two and a half years ago.Due to the serious loss of assets of the previous owner, the castle lacks daily maintenance.A major renovation was carried out before the owner of Page Island moved in. Perhaps a secret passage was secretly added that time?

The imminent need is not to find out how the secret passage came about, but how to keep up with it?What if there are people hiding below with guns ready to attack at any time?

However, there must always be someone who goes down the secret path first.

This time, Mr. Minton was not troubled, but three servants entered the tunnel successively.

After the frightening wait, there was no gunfire or fighting.

Five minutes later, one of the servants yelled, "Come on. There is something strange down there. Ferguson was impaled to death by a falling iron nail."

what's the situation?

The island owner of Page reluctantly got through the secret passage, and what suddenly appeared in front of him made him dumbfounded. This is a basement.At first glance, it looks empty, the four walls and the ceiling are completely black, and the ground is actually covered with metal.

The focus is on the center of the ground.

Ferguson fell in a pool of blood, with a heavy steel nail on his body.On his right hand side was a small hole sunken into the ground, containing a red-coated metal button.

His heel protrudes from a rectangular console with a roller-type alpha-combination lock.That is, 26 letters are engraved on one roller, and there are 15 locks in total.

"Oh! God!"

Wendy and Shipley worked together to lift the steel nail that killed Ferguson.I saw densely packed sharp iron nails, which adhered to Ferguson's flesh and blood, and there was a sentence written in black paint on this side.

"When the red button is activated, only the correct code words can prevent the island from sinking. Within 72 hours, there is only one chance. If you make a mistake, you and the island will be blown to pieces."

"Just kidding?"

A female guest shook her head in disbelief, "How could it be possible to plant explosives that can sink an island?"

Wendy shook her head with a pale face, "If you know enough about the geological structure of the island and use a lot of nitroglycerin, blowing up the castle to pieces is definitely not a threat."

As for whether the island will sink?

It's hard to say, maybe not, but the explosion... the explosion caused not only the collapse of the building, but also the attack of the shock wave on the human body.

Where did a group of people on the island go for refuge?

The island is very small. When the castle building was blown away, there was no other place to stay on the island.People want to escape the attack and must avoid the sea.

No boats, only swimming.

Not to mention whether the living people in the castle can swim, but the external environment is very unfavorable for evacuation, because the hurricane is coming.

Hurricane weather, people dare to swim in the sea?

That is no different from asking for death actively. In the next second, the wave is three feet high and the person will be swept away to nowhere.

Rumble!

Good spirits, bad spirits.The next moment, a thunderclap exploded over the castle.

Even being in the basement couldn't block the piercing thunder, as if thunder was exploding above the scalp through a layer of cardboard.After the thunder, the strong wind followed.The sound of turbulent waves hitting the shore resounded in bursts.

It's a hurricane, and it's coming early.

"Ah-"

Someone couldn't bear it and shouted out of control, "Fxxx! What the hell is going on! Who provoked the devil! Shipley, it's all your fault, how could you choose such a devil castle!"

One sentence ignited panic.

Shipley and the owner of Page Island were the first to be scolded. If the servants did not stop them, several guests would have punched directly.

"Hey! What are you doing?"

Wendy yelled while blocking it, "What time is it, you guys are actually fighting among themselves! Now we have to do everything possible to decipher the correct code."

"Decipher the code?"

Guest A sneered, "Hehe! Who deciphered it? Are you a detective writer? Okay, you break it, 15 roller locks, each with 26 letters. You have to turn 15 times correctly to stop the explosion. Whose Better at math, let's figure out what percentage of our survival rate we have."

What if you don't decipher the lock, but stop the explosion in other ways?

I'm afraid not.Due to the instability of explosives, the secret room has a solid metal floor that is difficult to dismantle.If violence is used, a group of people may be blown up during the demolition process.

Wendy subconsciously remembered someone who was not there, and almost blurted out to ask Mr. Minton to try.

As a detective novelist, I have more or less heard of Mr. Minton's previous crime-solving deeds. Maybe that one can create miracles again.

When the words came to her lips, Wendy held back.

No, can't say.Nominating anyone at this time is to bring hatred to that person.Even if you want to say it, take it easy.

For a moment, the secret room fell into dead silence and despair.

For a full minute, more than a dozen people seemed to have lost their breath.

It seemed that I couldn't even hear my heartbeat, only the infinite fear of approaching death remained.

"Go upstairs, don't all gather here."

The owner of Page Island recovered his voice first, "At least we still have about 70 hours to find the correct password. To deal with the hurricane first, we have to close the windows and everything. In the past two or three days, we still need a temporary habitat."

It seems that this is the only way to go.

People walked out of the basement in despair. If they found a kayak in the afternoon, they saw a glimmer of life, but at this moment, they lost it and made things worse.

Death is coming.

It has been dormant under the metal floor of the secret room, and when the time limit is up, it will harvest the lives of everyone on the island.

From the basement to the library on the fifth floor, the atmosphere is completely different.

Mycroft turned back to the bookshelf in the religion section. There were all kinds of classics on it, but the most well-known "Bible" was missing.

Is it because it is too popular, so it was not included?So why is the Bible still in Hubbard's room?

Because it was done on purpose by the murderer!

The "Bible" was not drawn by Hubbard from the bookshelf, it was placed on the coffee table at the beginning, heralding Hubbard's death.

'Squeak—'

The library door was pushed open.

"I've made a discovery."

"I found a clue."

The two spoke at the same time.

After looking at each other and smiling, Mary made a gesture of invitation, "Tell me first, did you find something in the library?"

"I found a lost oriental mathematics book. It is a pity that my shallow ancient Chinese ability cannot judge its authenticity."

Mycroft handed out the "Masculinity", "This reminded me of one thing, there is a sentence in the "Kings" of the "Bible" "He cast another sea of ​​copper, the shape is round, high five cubits, ten cubits in diameter, and thirty cubits in circumference."There is a number hidden in this sentence.and you?Got a similar thread? "

"I can give you a set of numbers."

When Mary talked about kayaking, "four kayak skeletons form a set of parallel lines with a row distance of 1 meter. Take a 0.5-meter-long broken arm and throw it on the kayak. Assuming that a large number of broken arms are thrown many times, the total It is thrown N times, and the number of times it intersects with the skeleton is K, so what is the value of N/K? Do you think this experiment is a bit familiar?"

Two people said two things.

At first glance, it seems unrelated, but at this moment, each other has obtained a definite answer, and both of them point to the same number.

Speaking from the "Bible", the "cubit" in it is a counting unit, that is, the length from the fingertip to the elbow is called a cubit.

Generally speaking, one cubit is 45.5 centimeters in the Old Testament, and 55.5 centimeters in the New Testament.In general, one cubit is about 50 centimeters, or 0.5 meters.

Mycroft refers to an excerpt from Shahnameh, in which the "copper sea" refers to the huge vessel used for washing, which is simply a bath.

The size of the copper sea in the book is almost exactly the same as the bath in Hubbard's room in the old castle.The castle bath is 2.5 meters high and 5 meters in diameter.

"Bathing is not the key. This sentence in "Kings" shows that people in ancient times calculated a value." ①

Mycroft mentioned, "A circumference of thirty cubits means that the circumference of a circle is 15 meters, and its diameter is 5 meters. Now we know that the circumference of a circle is equal to diameter x pi, but there was no such calculation formula at that time, let alone pi. "

Therefore, the diameter of ten cubits and the circumference of thirty cubits are reversed to give the pi approximately equal to 3.

Hubbard's death pointed out the "approximate value of pi 3" recorded in the Bible.

In contrast, the value of N/K asked by Mary is a more complicated mathematical calculation experiment.

In the 18th century, the French mathematician Buffon proposed the needle throwing experiment.

Throw a needle of length L between a set of parallel lines with a distance a.When 2L=a, the intersection probability of the needle and the line is 1/π.

The line of sight switches to the parallel skeleton of the fourteen broken arms of 0.5 meters and the kayak at a distance of 1 meter.

The N/K value proposed by Mary, as the number of throws increases, the more accurate the value of π can be calculated.

"The reason why we have to cut the severed arm to the same length is to restore this experiment, and want to express that we are calculating pi again."

Mary said and looked at the "Shushu" in her hand, "Although I can't judge the authenticity of the manuscript, I know one thing. The author of this book, Zu Chongzhi, discussed the value of pi as early as the 5th century AD. Research."

Although "Zhu Shu" was lost in the Northern Song Dynasty, it still has relevant records in the Sui Dynasty, and was selected into the Guozijian arithmetic textbook in the Tang Dynasty, which mentioned Zu Chongzhi's research on pi.

"On this small island, the murderer doesn't care about the wisdom of the ancients, or how the predecessors made precise calculations in that era."

Mary's tone was sarcasm, "The murderer behind the scenes only took the literal meaning to show off that he seems to know a lot, and he can penetrate Chinese and Western ancient and modern."

What literally?

This is related to the murder of Leo's grandson.

Zu Chongzhi is the upper line, what should the lower line do?

For Westerners in the 19th century, there was no instant search of the Internet, and there were very few people who could answer the second line.

Zu Chongzhi, Sun Xingzhe.

Ancestor and grandson are both surnames and correct seniority; Chong and Xing are both verbs;

One must be familiar with oriental culture if one wants to make an exquisite couplet, or listen to some allusions told by someone who is proficient.

The death of Leo's grandson is a clever response to this couplet.

"Just as Hubbard read the "Bible" before his death, alluding to his relationship with π. The ancestor and grandson were poisoned, and there was also a metaphorical clue left in the house."

Mary pointed out, "Sun Walker, the Monkey King in oriental mythology. Little Leo carries a monkey toy with him, and the monkey's eyes are poisonous chicken hen beads."

In this way, the three death events are connected in series, all related to π.

The eleven victims were carefully selected by the black hands behind the scenes.

According to their daily habits and work and life background, the way of death was tailored for them.

why?

Why does the murderer want to kill people related to pi?

"Mr. Minton, it's not your fault."

What Mycroft was talking about was the paper "π is a Transcendental Number" published at the beginning of the year. The argument put forward by Mr. Minton shocked the mathematics community.

"You know my strengths, and you never take other people's mistakes on yourself."

It was the nth time that Mary felt that her natural coolness was a blessing.The murderer may have arranged a castle killing game against her out of jealousy, desire to win, or messy criminal reasons, and killed innocent people as pawns.

These life debts should all be attributed to the murderer behind the scenes.

Having clarified the antecedents, I want to ask what's next?

What else did the murderer want?

Soon, the island owner of Page came to the fifth floor and got out of the mechanism lock of the underground secret room.

"Roller locks, each with 26 letters as a password. There is only one chance, and 15 correct letters must be entered to prevent the explosion from being ignited."

The owner of Page Island asked almost hopelessly, "The hurricane has come, can we still see the day when the sun shines?"

Mary and Mycroft glanced at each other. The 15-digit English-digital password is known to be related to pi.Perhaps, deciphering is not so difficult?

However, both of them maintained a serious expression, and did not show the expression of taking it for granted that deciphering might be easy.As a human being, sometimes you have to be low-key.