"Bring me a hammer!" Chen Xu commanded.

A craftsman standing next to him hurriedly went to the shed to get a hammer weighing five or six pounds, Chen Xu instructed the onlookers to get out of the way a little, and then smashed the cement brick a few times with his own hands, and found that it was really very strong, and it took a few hammers to smash a corner.

This hardness is no different from bluestone, even stronger than the toughness of bluestone, the main component of bluestone is calcium carbonate, which is soft in the stone material, otherwise it will not be used to make stone bricks in large quantities, the city walls and palaces of the entire Xianyang City are almost all made of stone bricks, terracotta bricks and rammed earth, which is the most commonly used stone, because bluestone is easy to process, but even if it is easy to process, the chisel made of bronze is still very worn. Moreover, it takes nearly half an hour to process a stone brick with a length of two feet and a width and a thickness of one foot, which is still in the case of a relatively regular stone, and a skilled worker and craftsman can not make much in a day, so at present, the stone bricks needed to build a large number of buildings in Xianyang are piled up manually, and there is no opportunistic trick at all.

But with cement is different, simply mixed with sand and gravel and water can be quickly poured out a large number of cement bricks and even directly poured in the mold, far more convenient than bluestone bricks, and the transportation is also convenient.

Chen Xu was very satisfied with the solidity of the cement bricks in front of him, so he went to carefully watch the various processing links and steps of the cement workshop, and made some more reasonable improvement instructions for some of the areas that needed to be improved, and finally came to the mill where the big iron mill was placed.

Said to be a mill, in fact, it is two clamp walls, three zhang wide and two zhang high, the sandwich wall is built with rough wood to build an operating platform, a funnel in the middle is just aimed at the grinding eye of the iron mill below, there is a small boom on the side of the sandwich wall, a basket of broken bluestone is hoisted to the operating platform, the worker slave shovels the gravel into the funnel with a shovel, and someone below drives the bullock to turn the iron mill, the stone will be ground into raw meal, and other coal iron ore and cement stone are finally also put into the iron mill to grind, When the large wooden basin under the iron mill is full, it stops to rest, and the workers come in to transport the ground raw clinker.

This pair of large iron mill weighs 5,000 catties, just to cast this iron mill took more than ten days, because never made such a large sand turning mold, pouring five iron-making furnaces at the same time to smelt the exact same ingredients of steel, using nearly 100 craftsmen to pour a success, and the success of the pouring of this large iron mill has also greatly improved the skills of the craftsmen of the iron-making workshop to pour large steel castings.

In order to drive this big iron mill, two strong bullocks are used, and they can't work too long at a time, but this is the current expedient measure, Chen Xu thinks that after the big waterwheel by the river is successfully manufactured, then he can use the waterwheel to drive the iron mill, but it is unlikely recently, because the water often rains and rises in summer, and most of the dam has been repaired and has almost stopped, and the waterwheel is still hanging on the riverbank, but it is considered that the waterwheel driven by the waterwheel can be designed and built first.

The cement workshop fired the cement that could achieve such strength this time, and Chen Xu felt that it had been completely successful, which was almost no different from the strength of ordinary cement in later generations.

And Chen Xu was also very touched in the careful inquiry, just studying the current state, the cement workshop has used more than ten craftsmen and dozens of apprentices nearly two hundred slaves, the tested formula has reached more than 30 kinds, and the finished products fired out have reached tens of thousands of catties, and the ground stone, coal and iron ore and clay are piled up, and the money and grain consumed during the period Chen Xu has not calculated at all, these are all Zhao Qing is in charge, and with so many manpower, material and financial resources, the hard work pays off, Although only a few hundred catties of cement products have been successfully completed at present, it is undeniable that this will be a major weapon that can promote the rapid development of the Great Qin Empire after steel, and will play an energy beyond the times in major infrastructure such as construction, transportation, and water conservancy.

Of course, in order to really let cement play the power of infrastructure, output is a huge bottleneck, but if you want to have Qin Da as the backing, if you see the effect of cement, even if Chen Xu wants to dig a hole in the earth, Qin Da will definitely not have too much hesitation, it doesn't matter if there are not enough people, Daqin Tieqi can sweep the Xiongnu and Donghu right now, is it enough to catch tens of thousands of people? If you don't have enough, you can continue to catch it, you can keep catching it until the Arctic and even the polar bear catches it to help grind.

Waiting for the concrete to set, Chen Xu followed Gong Shengsheng to the steel workshop and blacksmith shop next door to see the numismatic model and coinage press he had built in cooperation with hemp stick.

Qian Fan is relatively simple, because Chen Xu, Zhang Cang and a few craftsmen with experience in jade polishing and carving have designed successful patterns, plus a few craftsmen with experience in making Qian Fan and craftsmen who turn sand and mold making repeated trials, the mother model of the four coins of one coin, five coins, ten coins and fifty coins has been successfully cast, and the four copper coins with different materials have also been made with traditional techniques, and there is almost no difference in weight and design requirements.

Looking at the four coins of different sizes and colors placed on the fine linen, and looking at the exquisite and clear patterns on them, Chen Xu picked them up and looked at them carefully.

"Not bad, it's all designed!" After reading it, Chen Xu couldn't help but praise it repeatedly.

From the eyes of these coins, than half two coins at least several times more exquisite, especially the new coin of copper coins, the weight is more than half lighter, more compact and easy to carry, although it is still the same blue-gold round square hole shape, but imitated the copper coins of later generations have an outer ring, so not only to prevent someone from cutting off the outer ring to collect copper private coins, but also for wear-resistant and beautiful, and it is not just only half two or two small seals, but the front is engraved with the first emperor Tongbao four clear seal words, the back is engraved with the words of one coin.

The other five coins are cast in brass, pure yellow, weighing ten baht, belonging to copper yuan, no holes, engraved with a five-pointed star on the front, there are five seal characters of gold, wood, water, fire and earth on the five corners, a circle in the center of the back, engraved with a big Qin character inside, engraved with the words five coins on both sides, this money is called the five elements of the treasure.

Ten coins are cast in white copper, weighing fifteen baht, a gossip pattern on the front, a Qin character in the center of the back, and the words ten coins are written on both sides, this money is also called Bagua Tongbao.

Fifty coins are cast in copper, weighing one tael (twenty-four baht), the front of a yin and yang alternating Tai Chi pattern, the back is also a small seal of the Qin character, the outside of the ring arrangement of 'fifty coins of the first emperor twenty-nine years' words, and this money is also called Tai Chi Tongbao, because it is made of almost pure copper copper, it looks the most precious and gorgeous, the face value is also the largest, and it is the most convenient to hold in his hand, Chen Xu feels like he has taken a silver dollar of fullness, and he really can't put it down.

The molds for casting these coins are poured out of the hardest steel, and in order to make these four kinds of money models, the factory applied to Zhao Qing to call the best craftsmen who specially cast bronze for the royal family, and called the best mold workers, the best jade carving craftsmen, first made the finest and most realistic money fan style with paraffin, and then used the finest sediment to wrap the money fan into it by watering, and after countless times of watering and drying, a casting mold was obtained, when the melted steel was slowly poured into the mold, The wax fan melts and excludes from the pores reserved by the mold, and finally cools and opens the mold, and what is obtained is a pair of steel money fans.

This method of making molds with wax is widely used in the casting of bronzes, and has been widely used since the Spring and Autumn Period, and this method can be used to produce extremely complex bronzes, which is why so many bronzes with complex shapes and incredible shapes have been unearthed in later generations.

And with this money fan, you can directly use the most traditional method of coinage, pour the melted copper juice into it, close the money fan, cool it a little and open it, it is a complete brand new copper coin.

But Chen Xu was obviously not satisfied with such a primitive way of minting coins.

Therefore, a manual stamping mint was additionally designed.

A cast iron platform, a square hole in the middle, just half of the money fan can be put in, a piece of cast iron weighing fifty pounds above, fixed on the two steel columns on the platform through two round holes, can move up and down, a handle can lift and press down the cast iron, the other half of the money fan is fixed below the cast iron, put the money billet that has been made in the heat to the extent of softness, and then put it into the money fan of the stamping machine, press down the handle, under the weight of the cast iron plus the pressure under the handle, A coin is stamped out.

This press was not completed, because it was required that there should not be the slightest deviation when the upper and lower two dollars were closed, otherwise the coins that were die-cast would inevitably not meet the specifications, and at present, there would be gaps when the press moved up and down due to process problems, and the alignment effect was not very good.

In order to demonstrate the results to Chen Xu, the hemp rod and two craftsmen did it, put the finished money blank in the furnace fire to heat, and then one person used iron tongs to put the red-hot money blank into the money fan under the stamping machine, the hemp rod pressed down the handle, the cast iron above fell heavily, and then lifted the handle, and the other craftsman quickly took out the money fan below and gently knocked out the die-cast coins and threw them into the water basin, and then put the money fan into the square hole of the cast iron platform.