Lu An, who was far away in Danyang County, didn't know that Mifflin and Bachier's caravan was even smoother than he imagined.

The Hexi Trade Road, which connects the Central Plains and the Western Regions, has become smoother than before after he left Baishi Mountain.

In addition to the caravan escort composed of 100 orphans of fallen soldiers he left behind, the 300-person caravan escort led by Cheng Xuefeng played a great role.

In the area west of the river, even if there are sand bandits and forces from all sides who want to rob this caravan, they will have to weigh it in the face of the powerful caravan escort force.

After the New Year, the number of wild chrysanthemum grass roots and rock salt transported to and from Shiraishi Mountain by caravans increased exponentially.

After all, whether it was Mifflin and Bachier, or Fu Tianqi, they all knew that these two things would become a steady stream of wealth in Lu An's hands.

On the Yangzhou side, as always, there are people who keep transporting a large amount of sea sand and hay to Danyang County.

At the same time, limestone, calcite and charcoal are also being delivered to Jingyue Villa.

Among these materials, calcite is the most valued by Lu An.

This mineral, which is found in the mountains of the south, has historically been used in large quantities for medical purposes, but few people know about its other most important use.

Just after the fifteenth day of the first lunar month, in the Jingyue Villa, Lu An led a group of nearly 200 fallen soldiers and orphans trained by Mu Lingfeng, and they were constantly busy inside and outside the newly built kiln.

"Okay, the furnace temperature is almost up, add sea sand."

"Quickly bring the copper tube, dip it in the solution, be careful, blow gently!"

"Cut off the ends of the head and tail and put them in the mold!"

"This one is melted with calcite, cut with scissors, tiled, compacted!"

"Be careful, put it in that fusiform mold, be careful!"

On the busy site, Lu An pointed back and forth, and looked at the temperature in the kiln from time to time, and added potassium carbonate alkali noodles made of plant ash to it at the right time.

Lu An's knowledge of all aspects in his previous life was relatively complicated, but after all, it was the first time to make glass, although the process was simple, and the ratio of various materials required a little temptation.

One of the most important points is to increase the furnace temperature to lower the melting point of sea sand and calcite.

To reduce the melting point of sea sand, it is necessary to add the dose of potassium carbonate to the kiln.

In this era, there was no trona, and potassium carbonate could only be extracted from plant ash to replace it.

That's why he buys a large amount of hay, burns it to ashes, filters it over and over again, boils it again, and finally extracts the alkaline noodles.

Although Lu An was careful enough, the first attempt was still a failure!

The Army blew it itself several times and put it into a bottle mold made of metal.

Unfortunately, the final product still disappointed him.

However, in addition to him, including Lu Yuyan, Mu Lingfeng, Lian'er and others involved in the firing of glass containers, they were excited when they looked at the finished product that had been fired.

"It's done!"

"An Shao, we succeeded!"

After the glass bottle cooled down, Lu Yuyan screamed excitedly while carefully playing with the bottle in her hand.

Lu An shook his head with a wry smile, "Not yet, don't you see that there are too many bubbles in this bottle?" ”

He took another piece of glass that had just been made, and after breaking it, he picked up one of the pieces, pointed to the bubbles, and said, "Only after these bubbles are eliminated can it be considered a real success."

Otherwise, the firing bottle is very easy to crack where there are bubbles, and the thickness is uneven. ”

Despite this, however, Lu An was already mentally prepared for failure.

After all, the first firing of glass, some of the points, can only be slowly groped.

"Come again!"

Restarting, Lu An mixed the sea sand with more potassium carbonate and limestone, and continued to test.

For three consecutive days, it was fired more than a dozen times, constantly debugging the ratio of various materials, and at the same time increasing the frequency of stirring the glass melt, and finally fired a furnace of glass liquid without bubbles.

"Keep adding coal!"

In addition to the excitement, Lu An personally took the long metal pipe, continued to blow, and ordered people to cut off the semi-finished products blown into the metal mold one by one, and carefully handled the bottle mouth.

Lu Yuyan, Mu Lingfeng and Lian'er played with the cooled finished products back and forth, their faces full of surprise and excitement.

"Mrs. Lu, this kind of bottle made by An Shao is much better than the porcelain made by the Chen family!"

"Yes, Mrs. Lu, Miss, you see, the main feature of this bottle is that it is transparent enough."

"Well, I can't imagine that An Shao would come up with such a beautiful bottle made from something like sea sand, it's so smart!"

Listening to Lu Yuyan and Lian'er constantly praising Lu An, Mu Lingfeng's heart was sweet, and accidentally, the bottle in his hand fell off his hand and fell to the ground.

"Smack-"

After the crisp sound, everyone was stunned.

Lu An, who had just finished blowing a finished product, also looked at it.

Mu Lingfeng's face turned pale immediately, and he almost cried, "Xianggong, I ......"

Unexpectedly, Lu An waved his hand and smiled indifferently, "It's okay, there are a lot of these things, if you like it, just smash it, hehe." ”

Although Lu An said that he didn't care about it, Mu Lingfeng was still extremely distressed, and he didn't even dare to touch it anymore.

Lu Yuyan and Lian'er also broke open the metal bottle molds one by one more carefully, and lightly took off the cooled bottles and put them aside, for fear of making the same mistake as Mu Lingfeng again.

In fact, Lu An really didn't care, the glass bottle was already fragile.

Now that I've mastered the method, I can get as much as I want.

After about half an hour, Lu An handed over the blowing work to the others and began to process the finished products in the other two molds.

One of them is specially used to make glass lenses.

Before that, he had asked Lu Yuyan to contact and buy mercury.

As long as you have mercury and put tin foil on the glass sheet, you can make a real glass mirror!

Cut the glass molten flat, and then cut off the corners, it is a piece of glass.

Of course, for the time being, this transparent glass piece is not of much use to him.

The copper mirrors commonly used in this era are not only costly, but also have a poor reflection effect.

Therefore, the real value is the glass mirror!

It's a pity that in order to deal with the Plains Chen family, Lu An had to use more than half of the molten glass to make glass bottles to deal with the Chen family's porcelain bottles.

Otherwise, relying on the profits brought by the glass mirror alone will make him a lot of money.

Putting down the glass mirror, he carefully opened the fusiform mold on the side, revealing a convex lens the size of a pigeon's egg inside!