"It was during the spring ploughing, and I went home to help plough the fields, and worked barefoot with my uncle and sister-in-law. When I got home, I washed the dirt together barefoot. Then I found that when standing side by side, the feet of the three were long, the sister was the longest, I was the second, and the uncle was the shortest. The same is true in height, my sister is the tallest, eight feet, I am seven feet six inches tall, and my uncle is seven feet three inches tall. ”

At this time, I had a whim, found Qin Qi, measured the length of the feet of the three of us, and wrote down the number on the wooden board. After returning to the pavilion, I pondered it repeatedly, but I couldn't understand it. Until last month, there was no official business in the pavilion, and in my spare time, I found a calculation and tried to divide the height of three people by the length of their feet. I was amazed by the results, and the numbers I got were surprisingly consistent! ”

"Six and three-quarters! Ladies and gentlemen, this is the ratio of human height to foot length that I calculated! ”

Hefu slowly recounted his "experience" of discovering this, and said it in a conclusive way, as if it were true.

In fact, this was just an elective course called "Footprints" that taught him in the three years of the police academy in his previous life, but he went to every class and did not return all the knowledge to the teacher......

When he explained this, the four people of Joy, Anger, Happiness, and Anpu listened attentively, and Heifu did not have to worry that they did not know what "division" was and what "fraction" was, and it would be too much to underestimate the ancients if they really thought so.

The meticulous administration of the Qin State required a large number of officials who were proficient in mathematics, so there was a special teaching of "Book of Numbers" in the school. The officials in the Anlu County government, especially Cangcao and Hucao, basically memorized the Qin Dynasty version of the "Ninety-Nine Multiplication Table", but counted backwards from "Ninety-Nine Eighty-One". There is no way, who made their daily work to calculate all kinds of food and household registration.

Moreover, in these years, there have been fractional algorithms, including compound fractions (fraction addition), subtraction (fraction subtraction), multiplication (fraction multiplication), fraction (fraction division), and even lesson points (comparing fractions) and dividing (finding the average of fractions), except for the use of Arabic numerals, there is almost no difference from later generations.

After all, Li Si's fellow disciple, the great mathematician named "Zhang Cang", is now working in the Imperial History Mansion in Xianyang, Qin State, although the nine chapters of arithmetic were written in the Han Dynasty, in fact, they were born out of the accumulation of practical mathematics in the Qin State for more than 100 years......

Since everyone present had a bit of a mathematical foundation, Hefu was less tired of explaining. He succinctly threw out the figure six and three-quarters, and the next thing to do was to verify whether the ratio was reliable.

Everyone still hesitated, after all, although Qin Guolingshi recorded the size of the footprints in the case, most of them were compared after the culprit was caught, but rarely reversed, using the footprints to arrest the culprit.

So Heifu smiled: "In the past few days, I have tried several people in the Huyang Pavilion, and their height and foot length, without exception, have been divided to get this number, if you have doubts, why don't you try it too?" ”

"Okay, Chief Heifu, and use the length of my feet to calculate my height!"

Wei Shi Anpu was the first to stand up, he took a Qin ruler, took off his boots, measured his feet, and reported his foot size: "No more, no less, exactly one foot and one inch!" ”

Le is the best arithmetic among several people, so he pinched the arithmetic chips, which are some small sticks, which are quite complicated to use.

Seeing that he was struggling to calculate, but he did not rush to throw out the two things "Arabic numerals" and "vertical arithmetic", he knew that now was far from the time to offer them.

The system of the Qin State is too special, it is different from all previous dynasties, and those things from later generations are only worth offering when they can maximize their benefits......

It took a while for Le to come to the result: "Wei Shi's height is seven feet four inches?" ”

Anpu was still a little unconvinced, but when he learned the result, he was slightly stunned: "It's not much different!" ”

"Try mine!"

As Ling Shi, Nu has been dealing with footprints for so many years, but for the first time, he learned that the height of the murderer could be deduced from footprints, and he couldn't help but be interested.

Soon, the height of Nu and Le was also calculated from the length of their feet, and it was indeed similar to their original height.

"It's not even to the point of being perfect, but it's very close, Chief Heifu, you've discovered another incredible trick to solve cases......

Xi watched from the sidelines for a long time, and while affirming Heifu's discovery, he couldn't help but sigh: "If this technique had been done earlier, then over the years, many cases I have handled will be solved faster, and some vicious thieves will be able to escape and commit murder again." ”

Now that Heifu's "footprint method" has been proven to be reliable, the next step is to call up the "Sealed Diagnosis" recorded by that day's anger and look at the footprints left by the murderer.

At this time, Anpu also proposed that although it is true that the height can be estimated by relying on foot length, if you wear shoes, will there be a deviation?

Heifu looked at Anpu stepping on the deerskin boots used for riding horses, and said with a smile: "Wei Shi, those murderers and thieves are not comparable to officials, they can't wear good shoes, let alone shoes and boots, they can only wear hemp shoes." ”

It turned out that the shoes of this era mainly had the shape of 舄 (xì), boots, shoes and so on. Clogs were sewn with brocade embroidery, and were worn only by nobles who were not engaged in production. The boots were leather, and it became popular after the Warring States period with the Hufu cavalry, and it was common for officials and riders.

Most of the Qianshou soldiers are still straw sandals and cloth shoes, commonly known as shoes. Since the shoe is a shoe that only wraps around the foot, the error between the shoe print and the foot length is relatively small.

The "Sealed Diagnosis" was quickly taken, and according to the record of the day, the footprint was one foot and two inches long......

"According to the calculation that one foot of the Qin system is equal to 23.1 centimeters, the thief is a person who can wear size 44 shoes, what a pair ......of big feet," the black man sneered.

On the other side, Le also calculated the height of the thief, and said in surprise: "Calculated, after multiplying by six and three-quarters, the thief's height is about eight feet and one inch!" “

"1.87 meters, even if it is put in the future generations with better nutrition, it can be called a big man......"

The water came out, Heifu couldn't help but whistle, it's easy to find now, there will be no more than fifty people at this height, in Anlu County!

The height of the people of the Qin State is not shaped like the Terracotta Army, all of them are nearly 1.8 meters, maybe that is the standard figure of the people in Guanzhong?

Anyway, in Anlu County, Heifu found that his height of 1.75 meters was already considered to be outstanding, most of the county men were below 1.7 meters, and the nutrition in the township area was a little worse, and there were even many people who were only 1.6 meters tall.

It's no wonder, after all, the standard of adulthood in the Qin State is "six feet seven inches", about 155 centimeters......

After calculating the height of the "murderer", Le was overjoyed, and the mystery case that had been stuck in the bottleneck for a long time finally made a breakthrough.

Wei Shi Anpu is also gearing up, ready to take the county guard to search for the person who is tall and strong, and wears a sword, even if that person throws the scabbard and the sword inside now, it is useless, with their means, they will definitely be able to find a flaw.

The eyes that looked at Heifu became more and more admired, and he even felt ashamed that he had been making history for so many years, but he was repeatedly ashamed of Heifu's new methods. He subconsciously felt that whether it was the protection of the scene or the footprint law, it should be recorded and reported to the county government and the court lieutenant, so that they could become a practice, or even a law, and spread throughout the country!

Only Xi was very cautious, he took Le's calculation chip, and after he calculated it again, he found that the number "eight feet two inches" was correct, but he was not happy but worried, and his brows were furrowed even tighter.

"With that, there's a new problem."

He stared at the crowd:

"How did a man eight feet two inches tall jump into a window that was only three feet wide and commit murder?"

Heifu also discovered this flaw at this time, and suddenly broke out in a cold sweat, and realized that he had neglected an important issue.

That footprint is very fresh, it is indeed left on the same day, but is it really left by the murderer?

If not, why didn't the murderer leave his footprints when he climbed up to the window from the mud and strained his steps?

Everyone seemed to have been poured a scoop of cold water, and the excitement just now suddenly disappeared, and they all frowned and thought about it.

"There's another possibility."

Heifu's brain was spinning quickly, and he blurted out: "We thought about this case too simply. ”

"The murderer, most likely more than one!"