The snow was too heavy this winter, coupled with the resettlement of displaced people and other matters, the Jinyang Academy in preparation finally failed to open as planned, and was postponed to the beginning of February next year and officially opened.

However, before the New Year's Festival, Li Qi still began to teach the first batch of students who were preparing to become professors in the Hongwen Hall.

There were 30 students, all of whom were young officials under the age of 25 who were recruited or transferred from the Jin Dynasty and were preparing to participate in the imperial examination, compilers, proofreaders or students of the Hongwen Pavilion. Li Qi mainly wanted to teach them arithmetic in later generations, plus simple knowledge of geometry, physics and chemistry. Among them, chemistry was packaged by him as the alchemy of Taoism.

After all, this batch of preparatory "normal students" is already in their twenties, and they are also scholars, and their intelligence and understanding ability are far stronger than ordinary people, so they should be able to withstand high-intensity study and training.

Comparatively speaking, they are a little less hands-on.

Li Qi now has thirty-five students, thirty young "normal students", and four officials of the Hongwen Pavilion as auditors, plus Lu Bi, the general judge of Jinyang and the commander of the Hongwen Pavilion. Lu Bi's poems are very good, and there are ten of his poems included in "All Tang Poems", but he basically doesn't know anything about "miscellaneous studies".

Before the start of the school year, Li Qi prepared a set of four drawing and measuring tools for each student: a compass, a ruler, a triangle and a protractor. He intended to teach arithmetic as well as some simple geometry. After all, to apply what you have learned, the most commonly used are the four arithmetic operations and simple geometric knowledge.

The biggest difference between the classroom and the old school is that there is an additional blackboard, so that you can write what you want to teach directly on the blackboard, which is conducive to teaching for more people at the same time.

The first lecture is naturally the symbols in arithmetic, the numbers 0 to 9, these numeric symbols are not the Arabic numerals of later generations, they still use ancient Sanskrit, and Li Qi also stated that these numbers are Sanskrit numbers from Tianzhu. This is followed by "addition, subtraction, multiplication, and division", equal to, greater than, less than, parentheses, and so on.

Li Qi first wrote ten numbers from 0 to 9 on the blackboard, and then wrote the corresponding Chinese characters zero, one, two, three, and so on under these number symbols. After everyone knows these numbers by heart, they will begin to explain the concepts of individual, ten, hundred, thousand, thousand, ten thousand, one hundred thousand, until one billion, trillion, etc.

The next step is to apply the vertical form to perform the four arithmetic.

Fortunately, the scholars of the Tang Dynasty were not the corrupt Confucians who only knew the first four books and five classics in the Ming and Qing dynasties, and studied the eight strands of literature. However, it is limited to addition, subtraction and simple multiplication, and those who can skillfully apply the four arithmetic operations can be regarded as doctors of the Ming Arithmetic Department.

In the Tang Dynasty, it has always been one of the examination subjects of the imperial examination, and it can be regarded as a specialized knowledge.

In the Tang Dynasty, there are provisions in the "General Dictionary and Election", which is clearly calculated, and one of the "Nine Chapters of Law", "Zhang Qiujian", "Xiahou Yang", "Zhou Ji", and "Five Classics of Calculation" is tried, and six out of ten are passed; Try "Remember" and "Three Equal Numbers", and get nine out of ten to pass; I also tried seven articles of "Fixation", three articles of "Jigu", and six of the ten passes were passed.

In other words, in the Tang Dynasty mathematics exam, about 60 points can be regarded as passing. Ming arithmetic department and first, the rank of the appointment is from the ninth grade.

These primary school arithmetic knowledge of later generations seemed to be very simple, but in the Tang Dynasty, there were very few people who passed the Ming arithmetic department to raise the rank of Jinshi and the first. This also shows that arithmetic was a very difficult thing for the ancients.

Ancient mathematics, in addition to the naturally formed concepts of addition and subtraction. The concept of multiplication and division was formed relatively late, and the concept of multiplication in China can be found in the books of the Spring and Autumn Period, such as "three nine twenty-seven", "six six thirty-six", "seven seven forty-nine", "nine nine eighty-one" and so on. During the Qin and Han dynasties, these sentences were combined to form the original 'Nine Cause Song', which was the nine-nine multiplication table in later generations.

The concept of 'division' was not clearly put forward for the first time until the Three Kingdoms period, when Liu Hui annotated the "Nine Chapters of Arithmetic".

In later generations, the four arithmetic calculations that they had to learn in six years of primary school could be skillfully applied, and they were definitely considered masters for the ancients. Due to the lack of mathematical symbols, arithmetic calculus requires the use of so-called arithmetic chips, which are also very cumbersome to use. Therefore, those who are proficient in arithmetic can be awarded official positions for this.

Now, Li Qi has only been teaching for one morning, and the use of mathematical symbols and vertical forms has made the originally very complicated calculation process very simple.

Seeing the students in the class enthusiastically discussing and doing multiplication and division of more than 100 digits, Li Qi still felt a sense of accomplishment in his heart.

This is a good start, starting from this classroom, there will be a revolution in the history of mathematics in China, and a new chapter will be opened......

Well, it seems that I forgot to make an abacus.

Li Qi didn't want these students to only bury their heads in the classroom, so he made a plan to teach for half a day and practice in the workshop for half a day.

On paper, I have to learn shallowly, and I never know that I have to do it.

In particular, there are endless new tools, water conservancy machinery, and all kinds of ironware, cloth, cement and other new things in several Huangzhuang machine workshops, which are all commodities that can make a lot of money, and all of them are tempting.

The students were obviously more interested in the machine workshop than in the classroom.

It was very difficult for the ancients to keep any secrets, because they were very fond of communicating with people, and they also liked to show off. Maybe it's because of the division of labor that you need to work together to hunt for food.

It may be the reason why most people are afraid of being injured after going to battle, most of the generals Li Qi has seen are more fond of armor than weapons, of course, it may also be because the armor itself is about twice as expensive as weapons. Under the guidance of the blacksmith in the workshop of the Jin Palace, Yuan Ren finally tailored a pair of chain mail for himself. The steel wire mesh, which he had woven with his own hands, did not look as uniform and delicate as that made by the craftsmen, but it was nearly twice as fine, and the mesh seemed to be just big enough for an iron nail to pass through, let alone an arrowhead.

The materials were provided by Li Qi, but they needed to be made by hand, and Li Qi asked the blacksmith to give them a water hammer, and then let the generals of this gang toss around.

The chain mail made by the Li Family Iron Workshop is not entirely steel wire mesh, and the important protective parts of the body are also decorated with some forged thin steel plates of different sizes. The work of cold drawing steel wire is not done mechanically, but by manually shaking a reel like a wheel, and drawing the steel bar through the thick steel plate with round holes over and over again.

As for the production of chain mail, the craftsmen are not a little higher than Li Qi, and his only contribution to the entire production process is to "invent" the "vise" that can easily cut steel wires about 2 mm thick.

The latest standard chain mail in the barracks weighs only 16 pounds, and the thing that Yuan Ren made weighs 26 pounds. As soon as this half-body chain mail was completed, this guy put it on his body, and then appeared in the official room of the forbidden army in Jinyang Palace, which immediately attracted the envy and exclamation of a group of forbidden army generals.

Yuan Ren glanced at Shi Kang triumphantly, gestured at his chest and said to him, "Take a stick and knock it here!" ”

Shi Kang's eyes were also shining, holding a shovel handle in both hands, exhaling loudly, and when it was rounded, a stick smashed Yuan Ren's chest.

Bang!

Yuan Ren was smashed, and then grinned and laughed: "See, this thing is invulnerable, and it can offset most of the force on the stick, uncle, I will crisscross the battlefield in the future, like entering a no-man's land......"

……