Lu Xiangsheng stayed in Qingzhou Mansion for three days, during which he had a very happy conversation with Liu Yan.

When Lu Xiangsheng led his troops back to Jinan, Liu Yan also loaded the promised military equipment and handed it over to Lu Xiangsheng to take away.

After sending Lu Xiangsheng away, Liu Yan sent someone to find Song Guan and prepared to make a telescope.

The telescope is a must-have for marching and fighting, and it can gain insight and grasp opportunities from miles away, especially for artillery, and it is an artifact to increase accuracy.

Liu Yan had learned about Keplerian telescopes before crossing, although the name of this telescope sounds very professional, but its structure is very simple, just a combination of two convex lenses and two total reflection prisms, which can magnify distant images dozens of times.

This kind of simple telescope is enough for Liu Yan's current needs.

A few days later, Song Guan received an order sent by Liu Yan and rushed to Qingzhou Mansion with several skilled craftsmen from the glass workshop. 33

Liu Yan took out the sketches he had drawn, and asked them to grind out an 80 mm diameter convex lens objective and a 30 mm diameter convex lens eyepiece according to the drawings, and grind two total reflection prisms.

Those craftsmen were all "cadres" of the glass workshop, and they took the drawings provided by Liu Yan and studied them carefully for a while, and several people also discussed a few words in a whisper, and then nodded one after another, it is not difficult to make the things on the drawings.

Moreover, according to Liu Yan's order, everyone also brought a sufficient number of glass lenses from the glass workshop, including concave mirrors, convex mirrors, and plane mirrors, which were enough for the development of telescopes.

Liu Yan immediately arranged several empty rooms in the General Military Mansion as temporary "workshops" for Song Guan and others. Song Guan and a few craftsmen began to get busy, and after a period of grinding, the lens was polished in the afternoon.

Liu Yan was very happy to hear the news, came to this temporary workshop, personally measured the focal length of the two lenses, and then found a coppersmith to make a copper cylinder that was large in front and small in the back according to the drawings in advance, and folded in the middle.

"You put the objective, the prism and the eyepiece all in according to the drawing."

Liu Yan first compared it himself, and found that he still lacked this kind of hands-on ability, so he would give it to several craftsmen.

I saw a craftsman volunteering to fiddle with the lenses and copper cylinders, and it didn't take long for them to be ready.

Liu Yan raised the telescope and looked at the courtyard outside, and found that because the distance was too close, the effect was not very good, so he beckoned everyone to come to the city wall. I saw Liu Yan looking at the outside of the city, the telescope was completed, and Liu Yan clearly saw the small scenery in the distance.

"It's done!"

Liu Yan briefly estimated that although the structure of this imitation Kepler telescope is simple, the magnification is at least 25 times. Such a multiple would be a very rubbish existence in later generations, but in the current era, it is enough as an auxiliary device for artillery and an auxiliary device for battlefield command.

The Western telescope of this era was also newly invented, and it was extremely expensive. There are very few people who use telescopes on Daming's side, so Liu Yan can imitate the telescope by himself, which is already extraordinary.

With binoculars, when the battalions of the New Army do not accept at night and go out to investigate, they will get twice the result with half the effort. In the future, the battalions will not be closed at night, standing on a high place and scanning with binoculars, so that they can monitor movements within a few miles.

In this way, it is necessary to risk rushing to the vicinity of the enemy army at night, and the opportunity for hand-to-hand combat with the enemy's scouts is greatly reduced, which can greatly reduce the casualty probability of the elite of the new army at night, and can also greatly improve the ability to capture military intelligence information at night.

Not only that, but the telescope is an artifact for the artillery battalion.

With the help of telescopes, the correction of artillery shooting is much more accurate, and when the artillery battalion officers and men now make corrections, they mostly rely on their eyes, and many times they have to rely on personal experience and even luck. With the blessing of the telescope, the artillery officers can accurately estimate the distance between them, as well as the terrain and landforms near the enemy forces in the distance.

Even if the artillery battalion is deployed at a high place, the officers and men of the artillery battalion can clearly see the landing point of the artillery shells a few miles away with the help of telescopes, and can very intuitively check the effect of the artillery bombardment and judge the state of the enemy after being bombarded.

Of course, with this telescope, the generals of the new army can also better observe the situation on the battlefield, instead of just relying on the reports that are not collected at night to make judgments, after all, in the rapidly changing battlefield, any inaccurate news or delay will cause irreparable harm to the war situation.

It can be seen that the military value of this telescope is quite high, and Liu Yan decided that the telescope should be used as a top-secret material, which could not be sold to the outside world, and was only equipped with various battalions of the New Army. If a friendly force needs it, you can send a few as gifts when the situation allows.

Standing at the head of the city, Liu Yan said to Song Guan: "This thing will be called a telescope in the future, after you go back, you will organize craftsmen to carry out mass production, make thirty of them first, make them within fifteen days, and then escort them to Qingzhou Mansion by the soldiers and horses stationed there." ”

"Yes."

"Also, the production process of the telescope is also highly confidential, no one is allowed to divulge, you have to keep this in mind, all the craftsmen involved must be strictly guarded, the finished telescope, and the semi-finished products of the telescope must be registered and numbered, no one is allowed to take it out of the workshop at will, and those who violate the order will be punished as slaves and thieves!"

Song Guan trembled in his heart, and hurriedly clenched his fists to receive his life.

Twelve days later, the first batch of 30 telescopes made by the glass workshop was escorted by the soldiers of the New Army of Yiqi to the capital city of Qingzhou.

After Liu Yan inspected them one by one, these 30 telescopes were all well-made products, and the multiples of each one were about 25 times, and the error was so small that it was almost negligible.

So Liu Yan took out 25 telescopes and equipment for the commanders and commanders of each battalion and other senior generals, as for the generals such as Qianzong and Baizong, they will wait until the next batch of telescopes is ready.

In addition, there were five telescopes, which Liu Yan gave to the artillery battalion as the standard equipment of the artillery battalion.

Two days later, the commander of the artillery battalion, Qian Yan, came to report that the officers and men of the artillery battalion had figured out a way to use binoculars to aim and shoot, and asked Liu Yan to go and inspect it.

So Liu Yan ordered Qian Yan to bring a team of artillery, carry two Franc machine guns to the east city wall, and build a simple artillery battery here.

Liu Yan arrived here first, and then Qian Yan led a team of artillery battalion soldiers, drove a few horse-drawn artillery carts, and also went up the city wall along the road.

This improvised fort is located behind the arrows of the city wall, and the overall height is about two meters higher than the city wall, and it is a cylindrical pier.

"My lord, my subordinates have arrived!"

Liu Yan nodded, and briefly asked how the artillery battalion used binoculars to aim, Qian Yan explained briefly, but what he said was too general, and Liu Yan was not very clear when he heard it, so he said: "Then let's start, and play a few rounds of verification." ”

"Yes!"

Qian Jian immediately ordered his subordinates to start preparing for the shelling, only to see the captain of the artillery team use a telescope to look outside the city for a long time, and then said loudly: "One mile and five zhang ahead, the target forest, two doors are placed together, immediately filled!" ”

With the assistance of telescopes, the efficiency of ranging has been greatly improved, and the accuracy has also been improved a lot. It also provides gunners with information about the situation in the vicinity of the target.

"There are no pedestrians, no houses, safe and can be bombarded around the target woods!"

"The target forest is located in a depression, so you need to consider the launch!"

A squad of gunners skillfully operated two Franc cannons, and they used gauges, rulers, and moments to measure the angle of elevation and the amount of gunpowder, and opened fire on the target woods one mile and a half feet away.

The effective firing range of the Franc cannon equipped with the artillery battalion is about two miles, and now the trajectory of the target woods is basically straight when firing at a target forest of one mile and five feet, and if it hits a target about two miles or even two miles away, the trajectory is a projectile, and the shelling effect and accuracy will be reduced. But if the target is big enough, you can still hit it by adjusting the angle.

At that point, the importance of telescopes will be even more prominent.

"Good angle!"

"Loaded!"

The artillery captain used the telescope again to observe the target woods, the target composed of a dozen or so trees, still swaying in the wind, there was no one around, not even a single animal, so the artillery captain said loudly: "The target is clear, fire!" ”

The two guns roared almost simultaneously, and shells erupted violently in the tongue of fire. Liu Yan even saw the bodies of the two guns fall, and the shells shot into the distance at a speed invisible to the naked eye.

One mile and five zhang away, it was impossible to see the landing point of the artillery with the naked eye, but Liu Yan looked at it with a telescope, but he could see it clearly, the cannonball fell in the woods, and a cannonball even crashed into the trunk of a big tree that could only be surrounded by two people, and then the big tree broke off from the middle and fell down with a bang.

Liu Yan took off the binoculars, and a smile appeared on his face, he was still very satisfied with the effect of this shelling.

At this time, Liu Yan heard the artillery captain shouting loudly: "Correct three steps to the left, advance four steps, and fire!" ”

The gunners went up and dragged the gun mount and relocated the gun in the middle of the casemate. Based on the observation of the artillery captain using a telescope, the gunners readjusted the angle of the muzzle with moments and fired again.

The two guns opened fire again, and with a roar, the shells made an arc in the air and flew towards the target woods a mile away.

Then Liu Yan, Qian Liang and the artillery captain all saw the scene through the binoculars, and the two shells hit the target accurately, bouncing back and forth in the woods, and this shelling directly knocked down five or six trees!

Seeing this, the artillery captain excitedly shouted: "Hit the target!" ”

The gunners also jumped up excitedly and high-fived each other. If it weren't for the use of binoculars to assist in aiming, they would not have had the confidence to be able to hit a few trees from a mile and a half away, which is enough to make these gunners proud.

Some people died, but not completely......