Han Qian and his party rushed to the Mopan Valley camp and summoned Zou Lang, an engineer from the Works Bureau who had spent nearly two months conducting deep surveys of coal seams in the northern section of the Wujian Mountains, to understand the progress of preliminary work.

Currently, shallow coal deposits had been discovered in places like Datong Ridge deep within the Wujian Mountains. Local township offices had already begun organizing extraction, but the survey work on coal seam resources was still being conducted by Zou Lang leading a team.

This concerned whether subsequent development of the Wujian Mountain coal seams would be left to local township offices for small-scale operations, or whether the Pacification Commission would directly undertake large-scale development.

Although torrential rains continued in the mountains during June and July, Zou Lang and his team overcame difficult conditions and never interrupted their survey work. Currently, survey personnel at the Datong Ridge coal seam—most suitable for large-scale extraction—had already excavated several small exploratory shafts over ten zhang deep. The coal seam remained continuous with extremely abundant coal reserves.

The coal quality at Datong Ridge was also excellent, producing little smoke when burned, with few impurities and strong heat output.

Because the coal seam was elevated more than ten zhang above the surrounding terrain, even during this year’s rainy season, no spring water surges had been discovered in the Datong Ridge area. Even if there were any, drainage would be relatively easy, unlike coal seams in plain regions that would produce large-scale accumulated water difficult to drain.

However, Datong Ridge was nine li distant from Mawan River, a tributary of the upper Puyang River. This would require constructing nine li of rail track and two bridges with spans of approximately six zhang and eleven zhang respectively.

Of course, the Mawan River waterway was still somewhat shallow and narrow. During the dry season, transport capacity would greatly decrease, with possible interruptions in flow. But to build the coal transport dock directly outside the mountains at the Puyang River mouth on the eastern foothills of Wujian Mountain would require constructing thirty li of rail track. Using flat-bottomed cargo boats to transport coal, though not as fast as sharp-bottomed sailing ships, would not face capacity limitations.

Hardwood rail tracks, similar to railway tracks of later generations, had precedent dating back to the Qin Dynasty.

Even if the sleepers and guide rails were all made of hardwood, with specially designed horse-drawn carts pulled by draft animals running along them, the efficiency would be far higher than post roads and imperial highways that became muddy quagmires after rain when trampled. For draft animals pulling cargo carts, traveling on rail tracks would also greatly conserve their physical strength.

A large-scale coal field producing hundreds of thousands or even millions of dan annually would need to transport an average of three to four thousand cartloads of coal daily. Without relying on rail tracks connecting to waterway docks, this would undoubtedly be a disaster for ordinary roads. A single rain could bring transportation to a standstill, requiring enormous costs for constant road maintenance.

Of course, constructing rail tracks might not present technical difficulties, but the cost would be far higher than ordinary post roads. Setting aside other considerations, just imagine the expense of fifty to sixty thousand standard hardwood sleepers.

Zou Lang, leading a small team, had already drafted a preliminary rail track construction plan. Currently, the Wujian and Huaiyang Mountains had abundant hardwood resources like pine and cypress, eliminating the need for more expensive composite wood beams and precision iron tracks. However, initial calculations—including preliminary construction of the coal field and water transport docks—indicated the required investment of money and grain would be an enormous figure.

Even if the coal field achieved the projected annual output of six hundred thousand to eight hundred thousand dan of coal, considering this would cause coal prices to drop significantly from current levels, such a massive investment would take approximately ten years to recoup.

Of course, the accounting couldn’t be calculated this way.

In the current era, maintaining a massive urban population separated from agriculture required an astronomical amount of firewood just for cooking, drinking, and winter heating, not to mention casting, smelting, and other manufacturing work, plus firing bricks, lime, and cement—once scaled up, the fuel demand would be even greater.

If this fuel were to be replaced solely by logging and cutting firewood, plus agricultural straw, not only would surrounding forests be quickly consumed, but the required labor force would be unprecedentedly massive.

Using coal to fire bricks could reduce each brick’s price to one-third of its previous cost, with potential for further reduction in the future. This was primarily reflected in the difference in labor costs between obtaining coal versus firewood.

The predicament of the agricultural era was that besides cultivating sufficient food requiring arduous labor, obtaining firewood, weaving textiles, and constructing housing all required investing massive amounts of labor.

What Han Qian now sought to do was to significantly improve labor efficiency at every stage by all possible means, truly liberating the labor force to potentially escape the agricultural era’s constraints.

Whether the large-scale use of coal promoted the arrival of the industrial age, or whether it was the initial industrial revolution era that continuously stimulated coal demand and expanded its production, remained a subject of considerable debate in later generations. But undoubtedly, to some degree, they were mutually reinforcing.

After brief deliberation, Han Qian requested that Zou Lang and others conduct further surveys of the Datong Ridge coal seam and optimize the construction plan. However, he also required Feng Liao to immediately prioritize sleeper manufacturing without further delay.

Even if later confirmation showed the Datong Ridge coal seam unsuitable for large-scale extraction, the sleepers could be used elsewhere.

In his dream world, later generations had precedents for large-scale shallow coal extraction in the Huainan region.

Even if Datong Ridge proved unsuitable, Han Qian believed that Jiushan Mountain, Bagong Mountain, or other places in western Huai must contain large shallow coal deposits they had not yet discovered.

The terrain near Datong Ridge was not particularly rugged. Constructing nine or even thirty li of foundation road would not take too long. Rather, manufacturing tens of thousands of sleepers was no easy task. The firing of cement and casting of groove-type precision iron bridge beams all required advance preparation—in today’s Tangyi, this could be called a super-scale project.

Nevertheless, Han Qian strongly advocated doing it.

Only by doing it could technical details be accumulated and improved, while further cultivating and stockpiling engineering talent.

At the Mopan Valley camp, Han Qian conversed with Zou Lang and other engineers late into the night.

Just as they were about to rest, Feng Yi, who had just returned from Xu Province, arrived. Having failed to find Han Qian at Shiliang after rushing from East Lake, he rushed through the night to Mopan Valley.

After Huaidong handed over Shiliang County, Han Qian had transmitted orders to Xu Province requiring them to hand over the bandits trapped on Longtan Mountain to the Chen Province tribal camp for suppression, with Wei Xu and Lin Zongjing leading troops to supervise from the side.

The Chen Province tribal camp gritted their teeth and stormed Longtan Mountain, leaving not a single survivor, neatly delivering three hundred bandit heads without any discount—under these circumstances, even if the Xi family father and son substituted some ordinary tribal household heads, Feng Yi and the others could only hold their noses and accept them.

After delivering three hundred bandit heads, and under the supervision of Zheng Tong—a member of the Zheng clan sent by Zheng Chang as surveillance censor—Zhou Qinian and others, the Chen Province tribal camp finally departed Chen Province by boat along the Yuan River in early eighth month.

The Xi father and son had no choice. With Liang Kingdom in great turmoil and Shou Province forces temporarily unable to pose too great a military threat to Tangyi forces from the north, if they didn’t submit, even if they could withstand Xu Province forces’ attacks, could they resist Han Qian deploying another ten thousand elite troops from Tangyi?

More critically, Ye Province and Si Province both cowered under current circumstances. With Chen Province alone unable to stand, what Shen Yang and Zheng Chang had negotiated for them could already be considered the best terms possible.

After confirming the Chen Province tribal camp’s fleet continued south along the Xiang River toward Heng Province, Feng Yi took a boat back to East Lake first.

The Chen Province crisis that had lasted four and a half months was thus resolved.

As secretly negotiated exchange conditions, Surveillance Censor Zheng Tong would remain in Chen Province, replacing Xi Shesheng as provincial military officer. With Xi Shepeng accompanying the military expedition, his position as Xupu County Magistrate would simultaneously be assumed by Zheng Chang, also of Zheng clan origins.

Of course, with the tribal camp’s expedition, a batch of local official positions originally concurrently held by Xi clan members and leaders from other powerful families would be filled by promoting over ten non-native sons locally and dispatching appropriate officials from the Hunan Pacification Commission—this was a feast pleasing everyone except the Xi clan, Wanhong Tower, and Huaidong.

The county and township militia subsequently equipped in Chen Province localities for bandit suppression and maintaining public order, according to agreed conditions, would also ensure half were recruited from non-native sons, with total county militia scale limited to under one thousand men.

The greatest threat to Xu Province’s northeastern flank was thus temporarily eliminated. This also meant Si and Ye Provinces to the west would become more docile, certainly not daring to act rashly in the short term and provoke Xu Province, this fierce tiger.

After Feng Yi and Lin Zongjing led two thousand naval forces to reinforce Xu Province, Xu Province immediately lifted full alert, minimizing impact on production. Subsequently, naval forces would withdraw to Tangyi, while Xu Province active forces would further reduce to pre-crisis levels.

Feng Yi pursued all the way to Mopan Valley not only to report the good news of the Chen Province crisis resolution but also brought a special roll of oilcloth. Like selling treasure, he had it carried into the main tent and lit lamps to show Han Qian, Feng Liao, Han Donghu, and Huo Li:

“Xi Xunqiao specifically asked me to bring this over. Look what this oilcloth is made from?”

Previously, oilcloth produced in Xu Province mainly consisted of cotton-hemp woven cloth coated with tung oil for waterproofing.

Tung oil cloth was adequate for making oil-paper umbrellas, but costs were still high, with poor toughness and susceptibility to damage when used over large areas.

The roll of blue-black oilcloth Feng Yi brought emitted a slight burnt odor but could be determined to use hemp cloth as its base, also thicker and tougher than common tung oil cloth.

While Feng Yi and Wang Zhe frowned trying to guess what the coating layer was, Han Qian could smell that the burnt odor resembled asphalt from his dream world. He said: “The coating is pitch extracted through distillation from coal tar.”

To improve the quality of precision iron smelted using coal, Longya Mountain had long employed large-scale kiln-roasted coal. The pitch-black, viscous coal tar was a byproduct. For a long time, besides being used as a rust preventive coating on various precision iron components, no other use could be found for it.

Per dan of kiln-roasted coal, though only producing seven or eight jin of coal tar, several years of accumulation had filled an entire dry pond at Longya Mountain.

Coal tar’s use for precision iron component rust prevention required very little. Massive accumulation made it an extremely troublesome, difficult-to-solve major problem.

The Engineer Academy had been conducting dry distillation and fractional distillation treatments on coal tar.

The dry distillation method resembled charcoal production and kiln coal roasting—heating and decomposing while isolating air. Fractional distillation involved repeated heating and distillation; Yandang Spring liquor was produced using this method.

Previously lacking theoretical foundation, but after establishing the Engineer Academy, dry distillation, fractional distillation, and the extraction method for producing anti-miasma liquor became three important means for researching various material properties.

Han Qian knew coal tar had complex components. Only by separating different components could their specific uses be researched.

Han Qian had long known coal tar distillation could produce asphalt. In his impression, asphalt was used for paving roads. Using asphalt produced by fractional distillation of coal tar—a byproduct left from Longya Mountain’s kiln coal roasting—to harden road surfaces was obviously too extravagant in the current era.

He hadn’t expected Xu Province to actually use asphalt to coat hemp cloth, creating new waterproof cloth.

It looked particularly like oil felt cloth from later generations. He immediately became interested, inquiring about specific details and the actual cost of distilling asphalt.

Discussing production divorced from cost was meaningless. If the new waterproof oilcloth couldn’t be produced at lower cost than tung oil cloth, it had no significance.

He knew current detection methods were too limited. Undertaking large-scale fractional distillation production was equivalent to stepping into the most elementary chemical industrial production field, with danger too difficult to control. In his impression, coal tar contained many harmful toxic components.

Seeing Han Qian guess correctly at once, Feng Yi immediately lost interest. However, the Engineer Academy in Chen confirmed that large-scale distillation of asphalt from coal tar had neither high cost nor danger. At least for producing this waterproof, more durable pitch oilcloth, it was no more expensive than previous oilcloth.

For shed roofing and ship cabin waterproofing coverage, oil felt cloth had better waterproofing, moisture resistance, and damage resistance.

More importantly, compared to easily ignitable tung oil cloth, pitch oil felt cloth was far more difficult to ignite. On this point alone, in military fields prioritizing fire prevention, the new pitch oil felt cloth could completely replace traditional tung oil cloth for ship use, military camp waterproofing, and other applications, with usage quite substantial.

After understanding this, Feng Liao couldn’t wait to transfer personnel from the Chen Engineer Academy to East Lake to also organize production of the new oil felt cloth—East Lake’s kiln coal production had also accumulated considerable coal tar, causing worry about how to handle it.

Besides military use, this new oil felt cloth could also be sold in the capital region and prosperous provinces like Run and Hu. After all, even blue tile roofs, after years, still faced the difficult problem of rain seepage. In places like Tangyi, large-scale use of this pitch oil felt cloth would make simple shelter construction more convenient.

Of course, more importantly, Han Qian’s future fiscal tax revenue planning for Tangyi and Xu Province localities intended to leave field tax income—still comprising a considerable share at present—for provincial and county township office local use. With relatively sufficient local financial resources, local construction could be guaranteed without interruption. Market dock taxes, transit taxes, and other commercial tax categories, plus salt, liquor, tea, and horse monopoly sales, along with portions of profits from the Official Money Bureau, Works Bureau, and Chishan Association would be allocated to the Pacification Commission.

This meant Feng Liao had to rack his brains to increase new tax sources.

An industrial product that only Xu Province and Tangyi could produce at large scale and could be widely applied in a short time—how could it not excite Feng Liao?

—

Originally everyone had prepared to rest, but Feng Yi’s arrival caused chaos, and sleepiness fled like a thief without a trace.

Feng Yi had arrived at Tingshan at noon, eaten a meal there, then rushed nonstop to Shiliang. Not finding Han Qian, he rushed to Mopan Valley, already hungry with rumbling stomach.

However, the escort troops accompanying him had hunted a yellow sheep and a muntjac deer midway. Seeing everyone lacked sleepiness, Feng Yi pulled them together to find an open space, lit a bonfire, and skinned the yellow sheep and muntjac to roast over the fire.

Everyone ate with mouths full of grease until dawn broke, then went to sleep early, sleeping until afternoon before setting out for Datong Ridge to inspect the coal seam survey situation in person.

After walking through the mountains near Datong Ridge for three days, inspecting several mountain strongholds and two newly established township patrol inspector offices, they discovered the northern section of Wujian Mountain was simply a coal mountain. Besides Datong Ridge, shallow coal resources were distributed almost everywhere throughout the northern Wujian Mountain range.

Of course, traces of previous coal mining by predecessors were also discovered among the peaks and ridges of northern Wujian Mountain. But with frequent warfare in the Huainan region over the past century, the old affairs of predecessors mining coal and burning charcoal had already vanished into historical dust.

This showed how powerfully chaotic warfare impacted the entire society!

Regardless of whether large-scale coal mining would proceed in Wujian Mountain, the two newly established township patrol inspector offices in northern Wujian Mountain, governing nearby mountain areas thirty li deep with over ten villages and more than four thousand people, all needed a simple post road constructed. This would ensure contact between the two township patrol inspector offices and their affiliated Shiliang and Huailing Counties, also ensuring small-scale coal extraction could use ox and horse carts to transport coal via land routes to nearby waterway docks, spreading to more distant regions.

Though trekking tirelessly through Wujian Mountain, compared to the still scorching weather outside the mountains where blazing sun nearly burned grass and trees, inside the mountains with verdant trees it was quite comfortable.

Han Qian had originally planned to reach eastern Shou Province by the end of eighth month. Unexpectedly, on the eve of his planned departure from Wujian Mountain for Daishan Fort, torrential rain fell. Rain poured down from the vault of heaven like a waterfall, destroying the precipitous small path exiting from northern Wujian Mountain.

Torrential rains continued for several days—this was also rare heavy rain after entering autumn. Strong winds blowing from coastal areas toppled trees and collapsed paths in the mountains.

Besides first sending people out of the mountains to report and maintain contact, Han Qian, Feng Liao and others were forced to remain trapped in the mountains.

Not until the sixth day of ninth month, after the heavy rain ceased, did Han Qian and his party ford mountains and wade through waters, crossing the low ridges of northern Wujian Mountain to reach Daishan Fort, worrying all the way that disaster conditions in Chao and Hao areas would become more severe.

After reaching Hao Province, not only did Lin Haizheng—who concurrently held the position of Hao Province Governor, commanded Huailing, Linhuai, Zhaoyi, Zhongli, and Shou Province’s five counties, and was responsible for leading troops to press upon Shou Province forces from east and south—rush from eastern Shou Province, but Gao Shao and Wang Zhe, responsible for scouting and gathering Central Plains intelligence, also rushed from East Lake to Daishan Fort to see Han Qian.

This time Wang Zhe also brought the latest news from the Central Plains and Hebei regions.

In mid-third month, when Mongol cavalry and Han army infantry camps crossed the Taihang Mountains entering Ze Province, although Ze Province city was then under Liang forces’ control, the entire affair’s impact on Liang forces was too great.

Liang Emperor Zhu Yu commanded one hundred thousand troops in the northern expedition against Lu Province. The true main force troops were the thirty thousand elite horse and infantry troops of the Imperial Guard he personally led. Other troops were partly from the Southern Court Imperial Guards, partly provincial troops conscripted from various provinces and counties, and partly provincial forces requisitioned from Weibo.

With Bian capital’s rebellion, their rear route cut off, grain nearly exhausted, and prolonged unsuccessful siege of Lu Province city, with Jin forces ahead and barbarian horses behind, hearts filled with panic. Even if Liang Emperor Zhu Yu possessed the ability to overturn clouds and rain with a flip of his hands, he could only first ensure his direct elite forces retreated to Ze Province city, guaranteeing the Fen River valley retreat route connecting to Guanzhong region wasn’t severed.

At that time, even forcibly attacking and capturing Lu Province city had lost all meaning for Liang forces. They also dared not hastily engage in decisive battle with better-prepared Mongol main forces.

Lu Province city had been under siege for nearly a year, with food exhausted long ago inside the city. City fortifications outside, due to over a year of repeated plundering by Liang and Jin forces, had no more stored grain available for seizure. Moreover, two years of warfare plus Jin forces’ internal disruption had severely damaged agricultural cultivation in the Shangdang region, with large numbers of people fleeing into deep mountain forests or distant regions.

At this time, the northwest direction from Lu Province city—the mountain ridge pass leading to Taiyuan Prefecture—was occupied by the twenty-thousand-strong Jin reinforcement main force. The Jingxing pass in the northeast direction was blocked by several thousand Chengde elite troops.

Without grain supply, even occupying more cities in this territory surrounded by enemies on all sides was a dead end for Liang forces.

With outer troops successively routed and annihilated by Mongol cavalry, Liang Emperor Zhu Yu led the Imperial Guard main force, fighting entangled with pursuing Mongol troops in the Fen River valley until early sixth month before shaking off pursuers.

During this process, the Imperial Guard main force also suffered casualties and losses, troops declining to twenty thousand.

Liang Emperor Zhu Yu crossed the Yellow River, escaping into the Hejin region to rest for a month. At this time, rallying scattered and routed troops, sixty thousand troops regathered under his command—this was still because Liang Emperor Zhu Yu had timely detached elite forces to secure the Fen River valley passage and entangled Mongol forward elite cavalry as much as possible, allowing large numbers of routed troops to escape through this passage toward Guanzhong region without being completely slaughtered by Mongol cavalry.

Otherwise, even if the Liang Emperor’s Imperial Guard main force suffered no losses, escaping back to Guanzhong would be even more disastrous.

However, at this time, though Lei Jiuyuan, Han Yuanqi and others still firmly controlled Bian capital city, Hangu Pass west of Luoyang had fallen into rebel hands. Liang Emperor Zhu Yu’s passage leading Liang main forces west through Hangu Pass was temporarily blocked, temporarily trapped in Guanzhong.

After sixth month, Mongol forces also didn’t continue pursuing Liang forces along the Fen River valley.

In mid-sixth month, when Mongol Crown Prince Wusu Deyan and Southern Court Grand Preceptor Xiao Yiqing formed an alliance with Jin forces commander Liu Yun south of Lu Province city, they suddenly attacked and surrounded Liu Yun and his escorts. Twenty thousand Mongol cavalry then bypassed Lu Province city, trampled the Jin reinforcement camp north of Lu Province city, annihilated ten thousand Jin elite troops, then used camps abandoned by Liang forces to besiege Lu Province city once again.

The latest news came from Lu Province in mid-eighth month.

After learning Jin Crown Prince Shi Chengzu had pledged allegiance to the Mongols and was leading Shuo Province forces attacking Taiyuan Prefecture, the garrison defending Lu Province for over a year—with grain exhausted and morale doubly crushed—finally over nine thousand emaciated, skin-and-bones troops under garrison commander Tian Weiye’s leadership surrendered the city to the Mongols.

After Wusu Deyan and Xiao Yiqing occupied Ze and Lu Provinces, they detached more reinforcements crossing the Taihang Mountains into the south bank of the Yellow River, joining hands with Wei Province rebels to strengthen control over the Xingyang and Hanluoyang regions, blocking the passage for Liang main forces exiting Guanzhong westward. Meanwhile, they had Wang Yuankui, Tian Weiye and other surrendered generals lead their troops into Taiyuan Prefecture, joining hands with Jin Crown Prince Shi Chengzu to attack Jin Kingdom’s capital Taiyuan.

If no new incidents occurred, the fall of Taiyuan Prefecture and the Hebei, Hedong, Shangdang and northern Jin regions falling into Mongol hands was only a matter of time.

Due to Hangu Pass’s occupation by rebels and the Xingluoyang region falling into rebel and Mongol hands, Liang main forces were blocked west of Hangu Pass, unable to exit Guanzhong westward.

After Han Yuanqi and Chen Kun joined with Lei Jiuyuan and Jing Hao, though successfully preserving Bian capital, casualties from repeated fierce battles were extremely tragic. Currently only about twenty thousand troops remained, locked in stalemate confronting rebels east of Bian capital city.

The Sima clan led by Sima Tan chose to observe from Xu and Si regions.

Xu Mingzhen led Shou Province forces rushing nonstop to strengthen control over Ying, Qiao, Cai, Ru and other southern Liang provinces, neither revealing intentions to join rebels nor showing willingness to lead troops reinforcing Bian capital.

The entire Central Plains region at this time could be described as a tangled mess.

Of course, Gao Shao and Wang Zhe rushing from East Lake to Daishan Fort to see Han Qian weren’t simply reporting intelligence about Central Plains chaos.

During these days when Han Qian and others were trapped deep in Wujian Mountain unable to exit due to heavy rain, Shu Kingdom ruler Wang Jian sent envoy Wei Jian again to Jinling, proposing Chu and Shu forces join hands to participate in this campaign dividing Liang Kingdom…