Chapter 323: If He Needed It

Generally speaking, when people discuss technology, they can easily tell which technique offers the best performance.

But in actual practice, people do not necessarily favor the best-performing technique; in the end, they often choose the technique that suits them best.

Manufacturing artillery is the same. Taking the Hongyi cannon alone, cast bronze has better performance and can fire eight hundred times without failing; cast iron cannons are not as good — for the same caliber, they are twenty to thirty percent heavier and not as durable, designed from the outset to fire only six hundred times.

But the people who manufacture artillery often do not consider usage issues and focus more on cost. Twelve cast bronze cannons and sixty cast iron cannons cost the same — which one they would choose is obvious.

Liu Chengzong was an exception. Before the southern campaign, his controlled territory lacked iron mountains but had countless Buddha statues waiting to be reincarnated as bronze cannon bodhisattvas. It was not that he wanted to use cast bronze cannons, but that he controlled few iron mines and could only use cast bronze cannons.

But now that problem no longer existed. Xining Prefecture had discovered many mineral deposits around Qinghai Lake — gold, silver, copper, iron, tin, and lead were all far from scarce — so weapons could be manufactured using normal logic.

The iron core with copper jacket that Shi Chengwo proposed is a composite technique using a forged iron cannon bore and a cast copper cannon shell. The forged iron bore provides higher strength and toughness, while the cast copper shell exploits the self-tightening property of solidifying copper, increasing strength and toughness while slightly reducing weight compared to cast copper or cast iron.

In truth, this manufacturing method is not necessarily absolutely superior to cast cannons in strength; its greatest advantage lies in being easy to control.

Controlling cost, controlling material strength.

Forged cannons are not uncommon. Whether the early-captured Folangji small cannons or the Ye Gong divine guns created by Ye Mengxiong, both were forged from iron, giving the cannon body very high strength — but those were all small-caliber artillery.

Iron forging is extremely easy worldwide. As long as one can forge a knife or forge armor plates, one can roll iron into a gun barrel, and can also roll a fairly large iron shell to make a cannon bore, then forge iron rings one by one to sleeve over the bore — that is a Folangji cannon.

And for casting large bronze or iron vessels, ancient China had an accumulation of technique unrivaled in the world, even able to cast steel cannons as early as the Hongwu reign.

But it was hard to control. Pig iron, steel, and wrought iron were not clearly separated — it was simply that anything with carbon content above two percent was called pig iron, below 0.2 percent was called wrought iron, and carbon content between pig iron and wrought iron was called steel.

In this era, craftsmen could already increase carbon content during the smelting process and could also reduce carbon content during the smelting process, but getting exactly the right amount, no more and no less… was still not easy to achieve in iron smelting.

Because the world still had no method to completely liquefy steel. Even in the Central Plains, only a semi-solid liquid could be formed, and without being able to completely liquefy steel, there was no way to achieve precise control in steelmaking.

So under the vast majority of conditions, when smelting a furnace of iron, people could only guarantee whether the output was pig iron or wrought iron, but no one could determine whether there was any steel inside or how much.

Shi Chengwo's choice of iron core with copper jacket to manufacture mortars was partly for this reason. What Liu Chengzong required was a cannon with a large caliber and a short barrel. For other cannon-casting craftsmen, this might have been very easy — after all, bowl-mouth cannons from earlier years were exactly this shape.

But Shi Chengwo could not do that. He only knew how to cast Hongyi cannons and had no experience manufacturing other artillery.

Moreover, with the siege underway at this moment, to ensure success he decided to first cast a cannonball according to Liu Chengzong's caliber requirements, then forge the cannon bore to match this cannonball, and finally cast copper shells layer by layer over the iron core.

On the evening of the third day of the siege, just as the moat was about to be filled into a bridge, Choktu Taiji could finally hold back no longer. He dispatched over a thousand mounted troops to charge out from the south gate, attempting a night raid on the besieging army, only to run straight into Zhang Tianlin's main force training cavalry and had no choice but to retreat helplessly.

It is very difficult for any army to maintain organization during a night raid. When gongs, drums, banners, and signals all lose their function, a night raid can only be every man fighting for himself. So in reality, this tactic is a desperate kill-or-die move forced by asymmetric strength.

Choktu Taiji was in just such an awkward position. He could not win in a direct battle, and during several days of siege, his inferior equipment left him pinned down and beaten. The morale of his various tribes was extremely low, so he could only rely on a night raid to boost morale.

In truth, it was just trying his luck — using the darkness to drag the enemy down to his own level and see if he could win.

As it turned out, he ran right into Zhang Tianlin's patrol troops.

With Liu Chengzong prepared, how could it still be called a night raid? The raiding army returned without success, and morale sank even lower.

Soon, a hollow large iron cannonball five inches in diameter was cast by the craftsmen using the clay mold casting method. After receiving Liu Chengzong's approval, Shi Chengwo directed the craftsmen according to this caliber to forge the cannon bore, cut wooden fuses and wooden sabots, and sun-dry gunpowder.

In the commander's tent, Liu Chengzong held the large hollow iron ball, pouring the gunpowder inside bit by bit onto the table, and involuntarily swallowed.

This crudely cast cannonball weighed eight jin and twelve liang. After rough grinding, the irregular burrs on the surface were gone. It could hold four jin of gunpowder inside — just holding it in his hands felt terrifying.

It was essentially a round iron bottle for holding gunpowder. Liu Chengzong set the cannonball aside and picked up a five-inch-long wooden plug, peering inside. Through the small hole bored through the center of the wooden plug, he could see light coming through from the side at the bottom.

This wooden plug, wider at the top and narrower at the bottom, was the cannonball's fuse. Inside it, a perfectly fitted gunpowder cord had to be inserted. The method for making the gunpowder cord was the same as for corned powder, the only difference being that the powder was not made into grains but into a long cord.

Gunpowder made by this method burned at a uniform rate. At five inches long, there was roughly fifteen seconds from ignition to explosion.

In fact, based on experience with projecting explosive shells from flying-rocket cannons and the like, cylindrical explosive shells were the most effective because they would not spin inside the bore and cause accidents. But Liu Chengzong wanted to maximize the power of the blast, so he chose the spherical shape.

Liu Chengzong held the cannonball, looking at it and smiling, then suddenly slapped his forehead: "Bring brush and ink!"

In the commander's tent, Fan Sanlang hurriedly handed over the brush and ground the ink vigorously. In just a moment, she watched as Liu Chengzong drew circle after circle of lines on the cannonball, densely packed.

"Commander, this is…"

Liu Chengzong frowned in thought: "When this thing explodes, it'll burst into two or three pieces. When casting the cannonball, cast more grooves — thick elsewhere, thin along these lines — so it will crack first along the grooved places, creating more fragments to pierce men and horses."

He spoke with all seriousness, but in reality, whether it would work well or not, Liu Chengzong himself was not confident.

He was merely having Shi Chengwo attempt it. In any case, if it did not work, there was no loss. At the very least, he could be certain that four jin of charge would definitely blow the cannonball apart.

Even if it only burst into two pieces, that would still suit Liu Chengzong's original intent. If by chance those two pieces struck a trebuchet, four jin of gunpowder detonating at close range would be no less than a hit from a small cannon.

This cannonball, enchanted by Liu Chengzong with a brush, was quickly sent to the craftsmen's encampment, where the craftsmen further rushed to produce molds with pre-formed fragmentation grooves.

The following two days were quiet. The besieging side fired no more cannons, and the trebuchets inside the city also fell silent after hurling over a thousand clay projectiles. A rare calm descended outside Octagonal City.

Inside the city, however, Choktu Taiji was not simply waiting to die. He was merely waiting for an opportunity when Liu Chengzong let down his guard.

Although the early stage of the siege at the moat had gone poorly for him and his soldiers' morale was low, Choktu Taiji was not discouraged. Quite the opposite — he was rather pleased.

The herding soldiers inside the city had been busy these past two days picking up cannonballs, collecting over six hundred iron balls that had fallen inside the city, all seven-jin shot; outside the city, there were even more two-jin iron cannonballs, over nine hundred of them.

Back when he was getting beaten beyond the Gansu border, the Gansu Regional Commander had only fired this many cannonballs at him in total.

So Choktu Taiji figured Liu Chengzong was nearly out of cannonballs. He rushed to write a letter by the seventh day of the ninth month and had it shot out of the city.

This letter was quickly delivered into Liu Chengzong's hands. He opened it and read — the gist was that Choktu thought he was out of cannonballs and gunpowder. Could it be that you, Liu the Lion, are richer than the Regional Commander of Gansu? He urged him to quit while he was ahead and consider negotiating peace, letting him lead his army back to northern Suzhou, and he swore that in this lifetime he would never come to attack Qinghai again.

Liu Chengzong was utterly delighted by this letter. Never mind the matter of negotiating peace and letting him return to northern Suzhou — on the matter of military supplies alone, Liu Chengzong did not know whether he or the Gansu Regional Commander could mobilize more gunpowder supplies.

But he did know that the reason the Gansu Regional Commander used this amount of ammunition to hit Choktu was definitely because Choktu, in field battle, was only worth this much ammunition — absolutely not because the Gansu Regional Commander only had this much ammunition.

There are two kinds of saltpeter in the world that can make gunpowder. Potassium nitrate is everywhere in the northwest, and sodium nitrate exists wherever there are Gobi deserts, from Xining all the way to the Flaming Mountains.

Liu Chengzong also knew that on the other side of the sea there was a place called Chile, where the deserts were full of sodium nitrate — so much so that sodium nitrate was called Chile saltpeter. And the place with the largest reserves of Chile saltpeter was called… called Turpan.

This man must have lost his mind, daring to mock his gunpowder supply here in the northwest.

Of course, most people only knew that the northwest had plenty of gunpowder raw materials, but did not know that the northwest's reserves of gunpowder raw materials were this vast.

Liu Chengzong would never tell anyone this. Shili, the envoy of the Turpan Khan who had been kept by his side, still believed to this day that his homeland's specialties were melons and beautiful women.

Liu Chengzong thought melons and beautiful women were just fine. At least until that land fell into his own hands, they were certainly far better than gunpowder being the specialty.

In this cheerful mood, Liu Chengzong picked up his brush and wrote a Chinese letter of thanks to Choktu Taiji, inviting him to come out of the city and surrender, guaranteeing that as long as the Khalkha soldiers laid down their weapons and surrendered, no one would be killed.

He handed this letter to a guard. A search was made through the army — people who could speak Mongolian were easy to find, but those who could write the Mongolian script were few, and someone who could translate the letter of thanks from beginning to end was nonexistent. He had no choice but to send someone to summon Xie Erhu.

In truth, Xie Erhu had already requested to fight many times, but each time Liu Chengzong had refused.

He had never intended to let the Mongol troops under his command join the battle. Xie Erhu had no choice but to herd sheep in the rear and, incidentally, take charge of finding suitable pastureland.

Now, hearing that the Commander was summoning him, Xie Erhu changed horses three times along the way and galloped over at full speed. The moment he opened his mouth, he asked: "Commander, do you want me to beat up these Khalkha bandits?"

Liu Chengzong stared wide-eyed. You, Xie Erhu — the tyrant of Chuodan, a notorious desert bandit whose fearsome name even Liu Guoneng had heard of from Shili — have the nerve to call someone else a bandit?

Before he could speak, Xie Erhu had more or less figured out that being summoned this time wasn't for battle, so he said, "Grand Marshal, just let me go. I've been wanting to beat them up for ages!"

"You have a grudge?"

"I do!" Xie Erhu said, his face full of grievance. "The nobles under this Choktu robbed my grazing land and seized my Gold Sand River. If it weren't for them…"

Xie Erhu had started out quite angry, but as he went on, he couldn't help but grin. "Actually, heading east turned out pretty well."

Of course, the Xining pickled vegetables Ma Ke had picked out for him were only a minor reason. The more practical benefit was that following Liu Chengzong on one southern campaign had earned him more than robbing travelers in the desert for ten years.

As soon as Liu Chengzong heard it was an old grudge, he said no more about it. He raised his hand and passed the letter over. "A surrender appeal for Choktu Taiji. Make five hundred copies. Later, we'll fire them into the city with cannons."

Xie Erhu took the letter, his face twisted in displeasure. He lowered his head and muttered reluctantly under his breath, "Surrender? Let them reincarnate!"

Liu Chengzong didn't catch it. "What are you mumbling about?"

"Nothing. I was just saying, isn't the Double Ninth Festival coming up soon? How does the Grand Marshal plan to spend it?"

Liu Chengzong thought to himself, that's definitely not what he just said, but the remark was remarkably effective at diverting attention. He couldn't help asking, "You celebrate the Double Ninth Festival too?"

Xie Erhu shook his head like a rattle-drum, carefully watching Liu Chengzong's expression, before saying, "We don't, but everyone knows about it. The ninth day of the ninth month — that's the Han people's Double Ninth."

How did he know about the Double Ninth Festival?

Every ninth day of the ninth month, the northern and southern border troops in Suzhou would be on leave and their defenses empty. The common folk would climb the heights to pay respects to their ancestors, leaving their homes deserted. Seize the right moment to pull a job, and you could haul back several big cauldrons. The mutton stew was damn delicious.

But he absolutely dared not tell Liu Chengzong this. Erhu, with great cunning, believed that maintaining the image of a Mongol chieftain who loved pickled vegetables in front of the Grand Marshal was to his advantage.

Who knew — maybe one day, when the Grand Marshal was in a good mood, he'd grant him a fief in some place suitable for growing vegetables, all because of his love for pickles, and make him a Tusi.

That Chen Tusi in Xining had it pretty good. How comfortable — waking up every day only having to worry about problems like "I'm so poor" and "how to make money fast."

As a minor chieftain who had roamed as a nomad in Chuodan, he had simply never lived on that level.

Xie Erhu sat in the command tent writing the letters, his mind wandering as he imagined being granted a vast expanse of grazing land and a stretch of farmland in the future — farming and herding both, without conflict. After writing a couple of lines, he suddenly remembered something and looked up. "Grand Marshal, I know the Han people celebrate the Double Ninth Festival on the ninth day of the ninth month. Could the Taiji inside Eight Corner City know that too?"

Liu Chengzong was stunned by the question. "What do you mean?"

"We have to guard against it. We can't have the troops all go up the mountain to pay respects to their ancestors, only to come back and find he's made off with all the horses."

Liu Chengzong slowly shook his head. "No, what I mean is, he knows the Han people celebrate the Double Ninth Festival, but we don't."

In the years prior, the Lion Army simply hadn't had the conditions to observe festivals. Many holidays were spent either on the march or in battle — there was never a chance to celebrate. The only ones still kept now were a scant few: the New Year, Qingming, and a handful of others.

However, Liu Chengzong thought for a moment and asked Xie Erhu, "Erhu, are you saying it's possible that Choktu, seeing my troops head up the mountain, would know we've gone to pay respects to our ancestors, assume our defenses are lax, and seize the chance to attack?"

Xie Erhu nodded. It was entirely possible. Then, puzzled, he asked, "But didn't the Grand Marshal just say we don't observe the Double Ninth?"

"If Choktu Taiji needs us to."

Liu Chengzong paced a few steps inside the command tent, nodded to himself, and said, "I can observe the Double Ninth Festival."