Black oil is Yan Changwu's masterpiece, which is a black oil with a strong smell, called creosote, which is a product of dry distillation of coal.

Coal dry distillation is one of the important processes of coal chemical industry. It refers to the process of heating and decomposing coal under the condition of isolated air to produce coke (or semi-coke), coal tar, crude benzene, coal gas and other products.

There is a coal mine in Tainan, Yan Changwu has the knowledge of coal dry distillation, he needs coke to make iron, and the coal tar obtained from coal dry distillation contains a large amount of creosote, which can be used as a preservative, and then the coal tar is added with a gelatinous such as pine gum resin to increase viscosity, and it is also mixed with hair, which can be coated at the interface of the hull, and the ship board is directly coated with coal tar and resin, as an anti-biological coating, which can resist the erosion of ship maggots.

The bottom wood of the new ship is directly soaked in black oil, so that the ship wood can eat enough oil and can withstand it for a long time after launching.

Yan Changwu looked at the work of the workers and expressed satisfaction!

He asked Yan Shisan, the steward of the Yan Mansion who was traveling with him: "Have you paid enough for the Spring Festival?" ”

Yan 13 said respectfully, "It's all verified, it's correct, the hired hands thank the Overseer for his gift!" ”

In the world, there is a small institution in the Yan Mansion, called the "Supervision Office", which is served by the Yan Mansion Administrator and the Family, which specializes in checking the distribution of money, such as the army's salary, the government's grain, all the rewards and food issued by the government and the Yan Mansion, as well as the things sold by the people to the official, they are specifically responsible for verifying, if it is not right, they will find the parties to settle accounts.

At present, this mechanism is not bad, and the people in the supervision room are very effective, because if it is smashed, with their identity as "domestic servants", Yan Changwu can kill them with a cane!

Besides, we are pirates, and the pirate's favorite way is to invite people to the Dragon Palace as guests, and dare to deceive labor and management, so naturally labor and management cannot be blamed.

In the Ming Dynasty, punishing disobedient domestic servants is really not a thing, the government doesn't care at all when the head of the family is injured or disabled, even if the domestic servant is killed, as long as the power is big enough, the official government is the most meaningful, in the southeast mansion where the emperor is far away, Yan Changwu wants to punish whom, then who is called heaven should not be, and the earth is not spiritual.

But the servants don't need to worry and be afraid, Yan Changwu has clear rewards and punishments, rewards must have a reason, punishment must have a reason, he is not moody, killing and punishing from the heart, but pay attention to evidence.

As long as they work in the mansion and do it for a long time, Yan Changwu will send them to serve in the administrative center, join the army, do business, manage manors and factories, etc., and they will be given further training to adapt to the new position, which is written into the family rules!

Everyone has a head, and everyone doesn't want to do bad things.

……

There are two docks in the dockyard area, and in addition to the North Harbor No. 3, there are two smaller ships crammed into another dock for maintenance and repair.

As far as the long-term planning of a fleet is concerned, it is very important to arrange a dry dock to repair ships, and if the ship is well built, coupled with regular maintenance, it can be safely used for 50 years or more (not always immersed in water and sometimes sealed for more than ten years before re-entering the water), and the ship that is not well built and poorly maintained will collapse in a few years, especially the ship that is eroded by maggots will disintegrate in three months.

In terms of dockyards, Yan Changwu actually became the second in the world, and even the recognized maritime powers of the Netherlands and France could not compare to him! (The British built dry docks in 1495, the French did not open the first until the 18th century, Sweden in 1724, Denmark in 1739, and the United States in 1833.)

Then the maintenance ships of the countries before the dry dock, such as the wealthy Dutch, even brought the ship with the goods to the cargo owner, or directly dragged ashore for maintenance, which is troublesome enough.

……

After arriving at the dock in Beigang, Yan Changwu went straight to the Kaohsiung shipyard without stopping!

To be exact, the carriage does not stop, he also rides horses, but in the ruling area, he takes carriages in various places, and adopts Western-style four-wheeled carriages (the kind that can turn freely), at this time there are already shockproof spring plates, which are installed on the carriage, which are very comfortable, and the horses are running and resting, how good!

Kaohsiung Shipyard is the most important shipbuilding base of the Southeast Military Government, the shipyard is magnificent, and the construction of three sixth-class warships is almost completed at the same time!

On the dock outside the shipyard, three new warships have completed launching, outfitting and sea trials, and have been delivered, and are stationed near the dock of the shipyard.

The sixth-class warship is an agile three-masted schooner, with a gun deck with 18 guns, and 4 guns on the upper deck, with a displacement of 450 tons. There are about 180 members, and the cost is 25,000 taels of silver.

This is also the first batch of warships made in the southeast province, a total of 12 ships.

It was designed for cruising combat, had no cargo hold, and was therefore fast, in fact, it originated from a kind of Vergate clipper, built to be both slender and streamlined, with excellent sailing ability and agility to escape the pursuit of pirate ships and enemy navies.

Equipped with guns, Fergate's clippers became five-class sail cruisers and three-masted warships, which were mainly used to attack merchant ships at sea, cruise in the oceans, and act as the vanguard of capital ships.

The smaller clipper is the sixth-class warship of the Kaohsiung shipyard!

Building a sail warship is not an easy task, except for the warship that is under construction, there are many inland warehouses in the slipway, where ironwork, masts, sails, guns, and reserves are ready for use.

The shipyard was first selected for location, and Beigang was the initial landing site, but there was not much room for manoeuvre, and it was close to Penghu and facing the mainland, so the shipyard was located in Kaohsiung Town, which has the largest deep-water port.

The Port of Kaohsiung is located in Kaohsiung Bay at the southern mouth of the Taiwan Strait. Kaohsiung Bay is a long and narrow bay, 12 kilometers long, 1-1.5 kilometers wide, the entrance is only 100 meters wide, the shape resembles a pocket, the harbor in the bay is wide and deep, the wind and waves are calm, it is a natural harbor.

The port is there, the slipway and warehouse are built, and the ship is ready to be built.

After all, the carrying of heavy guns (usually pressing the hull) and firing (the recoil is ultimately offset by the hull) will exert strong pressure on the elastic structure of the wooden ship itself, and then there is the erosion of wind and waves, the attack of maggots, etc., for the warship, it is also required that its shell is strong and can resist artillery fire, and it is very particular about all aspects of the requirements of wood.----

Oak is the best wood for shipbuilding, most of the Western sail warships use oak to build their hulls, fully dried oak is durable, strong resistance to blows, and less wood chips, although Hongmaofan sometimes uses thick plates under the elm waterline, or also uses Cuban mahogany and Indian teak to build battleships, but oak is always the most important shipbuilding material.

Ancient Chinese shipbuilding mainly used camphor wood (Hainan, Taiwan and other places are very large) wood, such as Nanmu, shipbuilding will not use the hardest wood, it requires the first is corrosion resistance, as the saying goes: sun-dried thousand-year-old pine, blistered camphor.

Shipbuilding wood should have good toughness, high tensile strength, too brittle is not usable, but also low shrinkage, it cannot be said that after soaking in water and before soaking in water, the volume changes too much, it is not good (everyone understands the truth).

As for why we can't use too hard wood, for example, iron wood, known as invulnerability, let's take this example, we process it, just divide the wood to make the sawyman cry wet, five saw belts take turns, while sawing and grinding, a tree, hurt him for a day, the saw can't move, the tree nails almost don't enter, hard nails go in, it cracks, or the nails are bent and broken, nothing can be done.

Therefore, good wood may not be able to build ships, use good wood, thick and straight, and then meet the above conditions, the hardness can be stopped.

But Yan Changwu's new warship did not use camphor wood, he did not have the supply of oak, and he could not get teak for the time being.