Overall, resources are limited. The defense of Qiongzhou mainly relied on the strength of the Ming army itself.

After Shou Xian took over the command, the first thing he did was to inspect the entire coastal defense line in northern Qiongbei, and the fortifications of the defense line were based on the original coastal defense fortifications of the Ming Dynasty, and many bastions were added. Shou ordered to name this fortress line Qionghai Fortress.

All the main works of the fortifications are made of rammed earth, and each fortress relies on the topography to extend the acute angle fort outward, and some key points such as the wall foundation are reinforced with strip stone, red brick and pozzolana cement. The quality and quantity of volcanic ash on Hainan Island are average, and Zeng Ying can only grit her teeth and squeeze out some of the volcanic ash purchased from foreign exchange. Silver reserves were limited, and fortifications were built to tighten their belts. However, after the three-way soil is rammed and solid, the anti-solid bullet effect is quite good.

Along the way, I didn't expect Zeng Ying to operate the Qiongbei Defense Line so perfectly.

Shou Xu asked Zeng Wende beside him: "General Zeng, who presided over the construction of this defense line?" ”

"He Liangtao in Macau, his father used to be a patrol in Fujian, and he had a relationship with him when he surrounded and suppressed the thief Liu Xiang."

"This He Liangtao has fought?"

"In the seventh year of Chongzhen, He Liangtao praised military affairs in the army of Xue Bangrui in Wen, and participated in the suppression of Liu Xiang's remnants. My father once said that he was able to anticipate the enemy and was skilled in fire attack. ”

understands both actual combat and theory, and is a cattle man whose name was almost annihilated by history, holding his chin in order, "What about after Liu Xiang is killed?" ”

Zeng Wende sighed fixedly, "Lu Xiang, the governor of Xuanda, sent Mr. He to the Great Wall, but it's a pity that it's ......."

When it comes to Lu Xiangsheng, the order is clear, and He Liangtao's service experience on the Great Wall is probably not a very good memory.

"Has the Western-style platform been tested in actual combat on the Great Wall?"

"My father said that Sun Yuanhua tried to build an acute-angled platform at the gate of Shijiu, but he never saw it, but he only heard it. However, the squire Han Yun and Han Lin brothers in Jiangzhou, and Ma Weicheng, the squire of Xiongxian County, each transformed their hometown into a Western-style platform. ”

"How did they do it?"

Zeng Wende pointed to the greatly changed city wall of Lingao County in front of him, "Like us, build a positive enemy platform at the four corners of the city wall, build a plaque enemy platform in the center of the city wall, and build a single enemy platform at each city gate." ”

The enemy platform is the solid big acute angle fort of the four corners of the city wall, there are the nose, the mouth, the eyebrow, the eye, the platform, all the facilities are readily available, the eye is the part of the bottom of the fortress to the inward, and a small acute angle is formed.

The plaque enemy platform is a small acute fort added to the city wall, which was modified from the original Mamian Fort. The lone enemy platform is the half-moon fort that guards the city gate.

In the ninth year of Chongzhen, Xiongxian County was conquered by Jianjiao, and the local people fled into Baiyangdian without suffering too much loss of life. After the withdrawal of the army, the squire Ma Weicheng presided over the reconstruction of the Xiongxian fortress, and by the time of completion, Xiongxian had 10 acute-angled platforms, which was the only complete large fortress on the mainland. Since the fort was built, Xiongxian County has not been subjected to fire.

From the point of view of order, the origin of the Chinese fortress project, He Liangtao and Han Yun and others should also be the Italian military engineer Jacopo's "Della Fortificatione delle Citta" (i.e., "On the Fortification of the City") published in 1564. Castriotto, who had served as director of the French king's fortification works, was an authority in the field of fortress construction.

The castle did not completely copy the style of the Italian fortress, but made some improvements according to the local situation. In order to save earthwork, the height of each acute angle fort and half moon fort is less than the city wall, and it is more than 1 meter lower than the city wall. With the tower at the city gate, the tower of the Lingao Ridge Fort was also omitted.

"According to Mr. He, it is best to have the same height as the city wall, but the Qionghai barrier project is huge, and the speed of the construction and capture is too fast, so Mr. He lowered the height of the acute angle platform to complete it as soon as possible."

It can be improved in a timely manner according to the national conditions, saving manpower and money, but it does not have much impact on the defense of the fortress. This Mr. He is a master, and the order is becoming more and more interested in him.

Tsang Man-tak continued to introduce the life of Ho Leung Tao, who had lived in Macau for a long time, and the first half of his life was quite simple. Ho Leung Tao, a native of Renhe County, Hangzhou Prefecture, Zhejiang, grew up in Macau, believes in Catholicism, and has risen step by step in Macao to the chief five-person translation team in Macau, also known as "City Destiny".

Zeng Wende said: "Western cannons and Western-style guns, although Xu Guangqi and his protégé Sun Yuanhua knew what they said, they did not see their system. From his father's point of view, among the people he has seen, only He Liangtao is familiar with both cannons and guns. ”

Orderliness means understanding. If you just look at the picture, building a fortress is very simple. It would be nice to have a triangular fort extending out of the four corners of the city wall. The difficulty lies in the number of sharp angles set by the terrain. Although Xu Guangqi and Sun Yuanhua have long called for the construction of Western-style fortresses, they themselves do not understand these, so the Ming Dynasty has always thundered and rained little on the construction of the fortress, and there has not been much progress.

More than 20 years ago, when Ho Leung Tao was still young, Macau was invaded by the combined Dutch and British fleet, and if it were not for Manila's reinforcements of 4 galleons and 20 heavy artillery guns before the war, Macau would have been finished. This greatly stimulated the Macau government, and then the Portuguese built 8 fortresses of Patane, St. Paul, Guia, Guia, A-Ma, Ash Oven, Jia Silan, and Earl Ren.

Among them, St. Paul's Fortress is a four-corner fortress with a side length of 100 steps, the ash furnace fortress is a triangular fort, and the Horse Pavilion Fort is 150 steps long and 55 steps wide. The Macao fortress group basically completely replicates the existing fortress building technology in Europe, and all kinds of fortifications are complete. This gave He Liangtao a wealth of practical experience.

At the same time as the construction of the fort, the master foundry master Manuel Tavares Bocarro arrived in Macao from Goa and, with the assistance of personnel sent from Manila, built the Royal Cannon Foundry, the famous Bugarao Cannon Factory.

Ho Leung Tao not only had the experience of casting cannons at the Bugarao factory in Macau, but also personally participated in the design and construction of the entire defense system of Macau. , about the only engineer in China who understands both cannon casting and fortress construction. Sun Yuanhua's "Western Law Divine Machine", Zhang Tao and Sun Xueshi's "Western Fire Attack Artifact Theory", and even Guangdong General He Rubin's "Western Fire Attack Artifact Theory" are all translated from the "Practical Artillery Science Manual", during which there are many paradoxes, and when translating and copying, the misunderstanding errors caused by literati changing phrases at will abound, and the difference is thousands of miles, in fact, those books do not have much reference value. Only "Zhu Rong Zuoli" is written by He Liangtao, who really understands these things, and has high practical value.

Defend the order and step up to the Lingao Fort facing the northeast of the enemy platform, No. 1 Acute Angle Fort. The fort extends 10 zhang long from the horse face, and the left and right bottom ends are 15 zhang long. Three cast-iron cannons were erected on top of it, and the muzzles of the guns rushed out. Two large general cannons, which mainly fire shotguns, protrude from the bottom of the fort at acute angles to the two wings, opposite the plaques on the walls on both sides. The rest of the firearms such as bird guns and three-eyed guns are readily available. Although the weapon is a little worn and ugly, on this fortress, it is a sharp weapon for killing.

The three cannons are engraved with an inscription on the cannons, "Qiongzhou Mansion Haiphong Tongzhi He Liangtao supervised". The rough slit on the gun body is also a block model method that is convenient for rapid casting. It's just that the high-quality pig iron produced in Sanya gives this cannon a barrel life that far exceeds that of similar guns on the mainland.

Zeng Wende handed over the data sheet of the cannon.

The four parts of the gun size, the gun size, the ammunition consumption-range data, and the gunpowder formula are very detailed. Compared with "Western Fire Attack Artifact Illustration", only the amount of ammunition and "Western Law Divine Machine" does not have a gun ruler, which is much more comprehensive. Shou Zhi nodded frequently, which is written by a true insider. Sun Yuanhua and He Rubin didn't really understand artillery, and the books they translated did not focus on distinguishing between European steps and Chinese steps, and the differences between European pounds and Chinese catties in terms of weights and measures. There are many errors and omissions in the elevation angle and range data, if you follow the steps in Sun Yuanhua's book, the cannon will be loaded directly according to the European pounds of gunpowder in Chinese catties, 32% more charge, and it is really God forbid if it does not explode.

Shou Xuan gently tapped the cannon body, took out the ruler, and measured the divine power cannon himself. The gun has a total length of 285 cm, a caliber of 10.5 cm, a muzzle to the fire door of 234 cm, and a diameter of 22.3 times. From the muzzle to the tail of the gun, there are six iron hoops. The barrel weighed 1.5 tons and fired 6 pounds of iron bullets, which is about 8 pounds at a ratio of 1.32. The largest artillery in Qiongzhou has a caliber of 13cm, a length of 363cm, a muzzle to the fire door of 291cm, and a diameter of 22.4. Only 6 of these first-class Shenwei cannons were cast, and they were all placed in Haikou.

Most of the self-made artillery in Qiongzhou Mansion is the caliber of the cannon in front of him, which is the fourth class in He Liangtao's system, and He Liangtao has the most experience in casting 8-pounder guns, and the fourth class gun is a better combination of cost, man-hours and craftsmanship.

Lingao County has a total of 8 fourth-class Shenwei cannons, 6 of which are located in the two Jianjiao forts facing north, and 2 are located in the two Jianjiao forts facing south. With the close range firearms such as the Franc machine and the general owned by the local Ming army, it was already difficult to fight in this city. As long as the defenders have a certain determination, even if the Federal Army comes in person, they will have to dig the zigzag trench under the cover of long artillery, and the parallel trench will advance the large-caliber mortar artillery under the city wall to have a chance to take it.

Leaving Lingao County, Shou Xiang continued eastward.

The next important place in coastal defense is the Nato Inspection Division, which originally had a circumference of 170 zhang and a wall of 1 zhang and 8 feet high, including a 5-foot-high female wall, with a thickness of 7 feet to 1 zhang and 2 feet. There are 2 gates and 7 nests.

He Liangtao divided the fortresses of the Qionghai fortress into four categories, namely the Acropolis Fortress, the Weidi Corner Fortress, the Weidi Sharp Fortress, and the Weidi Semicircular Fortress.

The Acropolis Fortress is the four attached cities of Lingao, and the Weidi Fortress is an independent fortress built in the Chong Place, and the Nato Patrol Division City has also been changed beyond recognition. Compared with Lingao County, there is less of the Half Moon Fort guarding the city gate and the small sharp angle fort on the city wall, and the four main enemy platforms still exist, and they are equal to the city wall.

From the Lingao Natuo Inspection Division to the Chengmai County Chengmai Inspection Division, several square angular platforms were built relying on the beacons on the road. All of them are made of stone as the foot, and the wall is rammed into a three-way soil mixed with lime, sand and tile chips. The circumference of the city wall is 48 zhang, and the four corners are set up with acute angle forts, which are 1 zhang 5 feet thick, and 2 zhang wide on the left and right. The upper wall is made of women, more than half a meter high and 2 feet thick.

Shou Xiang walked into the main gate of the fortress from behind the platform, and there was a big house at the entrance, with the stairs for the personnel to go up and down on the left, and the slope for pulling the guns on the right, all of which were about 2 meters wide. In the center of the platform is a reservoir with a circumference of 8 zhang and a depth of 5 feet, which can hold about 64 tons of water. There are brick houses on the left and right sides of the pool, and the roofs are flush with the walls of the fortress, which is the ammunition depot of the fortress.

There is a culvert dug in the inner wall of the ring that is more than 2 meters deep, leading to the foot of the platform to facilitate drainage. There are 15 brick houses built on the terrace, which served as the residence and grain depot of the soldiers in the fort. The whole fortress is not big, only a hundred soldiers are needed to guard it, but it is simply armed to the teeth, even if the Eight Banners soldiers come to fight, they have to break a few big teeth.

For example, the square corner fortress, that is, the small quadrangular fortress, and the smaller fortress is the triangular fortress, that is, the pointed fortress. The height of the platform is 2.5 zhang, the front is high and the back is low. The city walls on both sides of the sharp corners are 10 zhang long and 8 zhang long at the bottom. There are small acute forts extending out of the two corners of the rear, about 1 zhang long. Its inner gate, ramp, pool, culvert, female wall, and ammunition depot are slightly the same as those of the Four Corners Fort, but the scale is slightly smaller, such as the pool can only hold 16 tons of water. This triangular fort is small in size, requires multiple mutual support to cover the beach, and the garrison is about 50 people.

The semi-circular platform is a harbor fort built on the mountain, a multi-layered fortress, and an artillery fan-shaped arrangement. It is more suitable to build in a condescending place with mountains and seas.

Taking the Chengmai Port Fort as an example, from bottom to top, the three-layer semicircular platform has a diameter of 15 zhang, 12 zhang and 9 zhang respectively, with a total of 19 large and small cannons and 70 soldiers defending Taiwan. Ammunition depots, pools and barracks are tailored to local conditions and there is no uniform standard.

After inspecting the Qionghai barrier in an orderly manner, he was very emotional. The quadrangular fortress is about the fortress of St. Paul, Macau, the triangular platform is from the ash furnace battery, and the semi-circular platform is from the A-Ma battery. All of them are excellent works that combine practical experience and local reality, Zeng Ying provides the stage, and Mr. He Liangtao pours his life's learning into China's last line of defense.