Chapter 83: Coast Guard

Marin's worry became a reality. Through the information brought by some merchants, he learned that the Frisian aristocratic republic across the sea was very dissatisfied with Marin's wantonly recruitment of Frisian fishermen.
Most of these Frisian fishermen's harvests were originally handed over to the Frisian aristocrats. However, when Marin recruited them, it was tantamount to robbing the interests of the Frisian nobles directly.
So, the parliament of the Frisian Noble Republic of Groningen is discussing whether to give Marin some lessons ...
Killing Marin, these Frisian nobles are afraid to do so, which will break the rules and offend the emperor and give the emperor an excuse to annex. However, it was no problem to send troops to attack Texel Island, to some of it, and to bring back the recruited Frisian fishermen by the way, and no one would gossip. Because, Marin snatched the Frisian fishermen first.
Marin certainly won't sit still, so he intends to strengthen the defense of Texel ...
Although Texel Island is an island, it is quite special. Because this island cannot be landed on all sides.
Mainly, two-thirds of the coast around Texel Island are shallow shallow seas. Whenever the tide ebbs, two-thirds of the shallow seas surrounding Texel Island become silty beaches. After the high tide, it became shallow. If ships are landed in these areas, they can easily run aground. Boats are fine. Big ships must not be near the coast in these areas, or they must be stranded.
On the entire island of Texel, there is only the Mars waterway in the southern waters and the area of ​​Odeshilde on the southeast coast. It belongs to an area with sufficient water depth, suitable for larger ships to dock, and suitable for landing.
Therefore, in order to prepare for the attack by the Frisian Aristocratic Republic, it is sufficient to defend the coastal areas south and southeast of the island. Among them, the focus of arming is on the two coasts of Tholencher and Oderschild and the nearby coast.
At present, the most effective way to defend the ships of the Aristocratic Republic of Friesland is to build a battery. The turret can be equipped with heavy artillery and bombard with enemy ships.
Moreover, the turret is generally built of stone, and has a strong ability to resist iron ball shells. But ships are different. The current ships, until the mid-19th century, were all wooden hulls. The anti-strike capability of iron ball cannonballs is very limited. Wooden warships and coastal artillery in stone fortresses are bound to suffer. In addition, shore defense guns can be made very large and very powerful. The artillery on wooden boats is often greatly restricted and cannot be made too heavy. Otherwise, the boat is equipped with a cannon, and the recoil of the cannon may overturn the wooden boat.
As a result, Marin immediately clapped and built shore defences at the two ports of Tholencher and Oderschild to prepare for a possible attack by the Frisian aristocracy.
Texel Island does not have the ability to make guns, nor the artisans who make guns. Right now, at the end of the 15th century, the artillery craftsman is definitely a top talent in Europe. Even in those big countries, artisans who can cast guns are high-end talents. Marin can easily recruit artillery guns, but it is difficult to recruit artillery craftsmen. Therefore, he can only choose to buy artillery.
For this reason, Marin sent a manpower and hired Jewish merchants to help them inquire about the source of the artillery ...
After inquiring, Marin learned that the level of the Holy Roman Empire's cast guns was average, and only small bronze guns could be cast for land warfare. This is because the Holy Roman Empire was a land-based country. Moreover, in the southern part of the Empire, close to the Alps, artillery needs to be portable and able to cross the Alps. Therefore, artillery cannot be cast very large. The artillery required for coastal defense turrets must be heavy artillery. Therefore, the artillery of the Shen Luo Empire clearly did not meet the requirements.
In addition, France is also a country that attaches great importance to casting guns, and has good casting gun technology. However, Marin lost his face because of Charles VIII. Therefore, it is impossible to buy guns with the French.
Therefore, Marin could only look at other countries-Britain, Portugal and Spain ...
However, the feedback from those sent out is not good ...
According to the feedback from the people who sent to Spain and Portugal, Spain and Portugal are currently the most popular bronze after-loading guns-the so-called Fran machine guns in the Ming Dynasty.
This gun has a range of only 2,000 feet (666 meters, recorded in the Ming Dynasty). It is definitely not suitable for shore defense guns. Even if used as a naval gun, the power is slightly small.
However, because the sailing era has just entered, the Europeans have not paid much attention to the power of naval guns. Therefore, the popularity of this small-powered bronze cannon is also reasonable. The development of European artillery technology was about the 16th century. Due to the needs of naval battles, heavy artillery such as "Hongyi Cannon" was developed.
Moreover, bronze artillery can't be made too big. Because bronze has a major flaw-it tends to soften when overheated.
The smaller caliber bronze guns are fine, the larger ones are different. Large-calibre artillery has high bore pressure. When the barrel was overheated, the gun wall became soft. Although the bronze is not as soft as pure copper after overheating, it eventually softens. The small bore caliber pressure is good. Because the large bore gun has a high bore pressure, it is easy to deform the inner wall of the barrel when firing under overheating conditions. In this case, the artillery is useless.
Therefore, bronze guns cannot be cast too large, only small and medium-sized ones. Want to cast heavy artillery, can only choose to cast artillery with iron. Moreover, cast iron guns are much cheaper than bronze guns. After all, European copper prices were expensive until the development of the Swedish copper mine and the Dutch acquired Japanese copper. Casting heavy guns with a large amount of copper is absolutely costly.
Marlin was originally disappointed, but there was good news from Britain ...
The personnel sent to the United Kingdom to buy artillery were divided into several groups. The first few people did not bring good news. But the men and women sent to Sussex (or Sussex) in Britain brought back the good news.
Sussex is located on the southeast coast of the United Kingdom. Since Dijon in France produced cast iron in the middle of the 15th century, this technology has gradually spread, and more than a decade ago, it reached Weald in Sussex, which faces France across the sea.
As a result, artillery founders in Wild, Sussex, began experimenting with casting iron using cast iron. Because cast iron is much cheaper than bronze.
十几 After more than a decade of trials, Sussex County's gunners used cast iron blocks to cast a cast iron Kofelin cannon.
According to the descriptions of the staff, this type of cast iron gun under test is a 12-pound gun. Originally, the old gunner Johnson wanted to cast an 18-pound Kofelin long-barreled gun. However, cast iron technology of this era ...
老 When the old Johnson cast adopted the 18-pound caliber, because of steel quality problems, the gun barrel often exploded. As a result, Johnson's nephew was also seriously injured and disabled. In desperation, the old Johnson had to reduce the caliber without reducing the total weight, making the cast iron gun a 12 pound class.
Old Johnson nearly exhausted his fortune in order to develop such a front-mounted heavy-duty cast-iron cannon. Right now, he has only made preliminary progress. Old Johnson's goal was to upgrade the cast iron gun to a 18-pound gun. Then, use this unique technique to find the king ...
"The 18-pound Kou Feilin's long-barreled gun ... Is this ... the legendary 'Hongyi Cannon'?" Marin was taken aback.
He remembered that the first batch of Hongyi cannons that the Portuguese sold to Daming more than a century later appeared to be 18-pound Kofelin cannons salvaged from a British sunken ship. And this old gunner named Johnson is probably one of the earliest developers of the Hongyi Cannon ...
"Talent, you must not let go!"
As a result, Marin ordered that someone be sent to Weld, Sussex, England, to invite the old Johnson family to Texel Island, to cast guns for Marin.
Marin's men have long inquired, because the British "Red and White Rose War" still has its aftermath, and Henry VII is still anxious to clean up the domestic opposition. Therefore, he hasn't noticed this one. And the old Johnson, not a regular and royal caster of the kingdom, was just a folk caster who had worked with regular craftsmen to cast the gun. Moreover, the old Johnson's cast-iron cannon has not yet been finalized and recommended to the kingdom, let alone adopted and valued.
Therefore, the old Johnson is still not a British national treasure-level gunner. Therefore, it is not difficult to recruit old Johnson, at least it will not be blocked by British officials.
Marlint sent Heidel Lehmann, Mayor of Den Burg, to lead the team to Weld, Sussex, to secretly solicit the old Johnson family. After giving young men of the old Johnsons a "high salary" of 1 shilling per day (the average daily wage of a craftsman is only 3 pence), Johnson, the family of cast guns, moved to Den Burg on Texel as a whole and started to specialize Lin Zhuao.
As for the problem of the old Johnson bombing problem, Marin actually already has a solution. The bombardment of a cast iron cannon is nothing more than pig iron used in the cannon, which has too many impurities, such as sulfur and phosphorus, which results in the artillery barrel being brittle. In addition, pig iron has too high a carbon content, and although it has high strength and insufficient toughness, it is not suitable for casting guns. What is really suitable for casting cannons are actually wrought iron and medium and low carbon steel.
马 Although Marin is unprofessional about how to make steel, he has also learned many theories from many novels. For example, he knows that an important secret of the early British iron cannons that were not easy to blast is the use of a reverberatory furnace for secondary refining of pig iron.
The so-called reflection furnace is a relatively closed furnace (including air inlet and air outlet). After the pig iron and scrap iron are put into the furnace, the heat in the furnace cannot be dissipated because of the relatively closed space. After reaching the furnace roof and the furnace wall, they are reflected back to concentrate the iron. After several hours of refining, plus some slagging agents (the simplest slagging agent is quicklime, which can be used to remove sulfur and phosphorus). Then, after cleaning up the waste (due to the density problem, the waste is usually floated on the molten iron, it can be removed by fishing), and then wrought iron or steel is obtained (the carbon content needs to be controlled).
The well-known steel-making open hearth furnace is actually a heat storage chamber inside the reflex furnace.
The British Empire fully mastered the refining furnace refining technology in the 18th century, which also made the British-made iron cannons of good quality and difficult to blow. And because the French did not understand this technology, until the early 19th century, naval guns were still easy to bomb. It was not until the middle of the 19th century that France and other European powers initially learned about refining furnace refining technology. But then, the open hearth appeared, and mankind entered the age of open hearth steelmaking. The artillery has also entered the era of forged guns from cast cannons.
(The so-called forging gun is to place the steel column under a large hydraulic press of thousands of tons or even tens of thousands of tons, and press hard cold forging to make the internal structure of the steel column extremely compact and strong. Then, A good steel column is drilled with a high-strength drill bit to obtain a very strong and durable gun wall. The cast artillery, because the molecular structure of the gun body is relatively loose, can withstand a bore pressure that is greater than that of forging of the same volume The gun is much lower. Therefore, in the early foundry guns, the gun body is generally thick. The modern forged guns are relatively thin.)
Marin is not a steel major, but I have read a lot of related technical posts. UU reads www.uukanshu.com He won't do it by himself, but he will direct others to do it.
The structure of this reverberatory furnace is very simple. He could command the craftsmen to make one, and then make high-quality wrought iron and steel. Then, using wrought iron or medium and low carbon steel to cast cannons is definitely much better than cast iron cannons with a lot of impurities in this era, and it is not easy to blow the chamber.
Of course, the reverberatory furnace technology is an "advanced technology" that only appeared in the 18th century, and Marin naturally cannot reveal it casually. So he considered using serfs with restricted freedom to do this. Because serfs could not leave their place of residence at will, and had no conditions to leak technology out. Even the life and death of the serf's entire family are in the hands of the lord, and the risks and costs of betrayal are enormous. Artisans recruited like Old Johnson are free in identity. If someone else pays a high price, he may be tempted to leak the technology. Moreover, before coming to Texel, Old Johnson signed an agreement with Heidel Lehman, stipulating that Texel must not restrict their personal freedom. In this regard, Marin must also abide by the contract. Otherwise, he would not be able to recruit more artisans.
Of course, those are the last words. The most important thing for Marin right now is to let the Johnson family first help him cast more 12-pound cast iron guns for shore defense.
At the moment, three-pound guns, four-pound guns, and six-pound guns are more popular in Europe. More than 10-pound guns are considered heavy artillery. Marin used a 12-pound gun at the coastal fortress, which was absolutely enough to suppress the warships of the Frisian Noble Republic.
Because, according to information, the largest caliber artillery on several warships owned by the Friesland Aristocratic Republic was only a 6-pound gun, and it was not an opponent of a 12-pound gun.
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