The murals on the cliff face depicted not only a river and a towering tree, but also two mountains facing each other across the riverbanks. The outer slopes of these mountains stretched endlessly, while their inner faces were sheer cliffs, carved as if by a knife, their height and peril defying description. The great tree grew between these two closely spaced peaks, its massive branches extending outwards to rest upon the cliff walls, forming bridge-like pathways. Upon these bridges, in addition to cascades of vines and canopy-like foliage, were groups of ancient humans, clad only in grass skirts, mimicking various animals with different expressions... This truly bore a striking resemblance to the drawing on the silk manuscript. Yet, on several colossal branches of this very tree, we spotted funeral processions!

Strictly speaking, it was an entire burial ritual, beginning with the construction of the coffin. On one enormous branch, dozens of robust men were using axes and knives to hew a very thick bough. These men were clearly working in concert: some were stripping away the smaller offshoots, while others were bent over, digging hollows into the branch using a tool whose name I couldn't recall... On a branch directly above this one, a coffin, already shaped, was being carried by seven or eight sturdy men. It seemed they were heading towards the precipice at the edge of the canopy, where a jutting piece of mountain rock awaited at the branch's end.

Frankly, I lack the vivid words to describe what was happening on this colossal tree. It was an entire human society, in microcosm. I cannot perfectly convey the intricate details of those burial rites, but I finally grasped a truth—ancient suspended coffin burials or cliff tombs were not as complex as modern people imagine. They simply utilized their immediate environment, following the natural contours of the land. Perhaps they never considered that this act, born of both piety and convenience, would puzzle later generations for so long.

I have always considered myself sharp, but I must now admit I overlooked a fact I should have realized much sooner—the coffin we just sat in might have been fashioned exactly as depicted in the mural: carved and hollowed out from a living branch of the current tree.

If this mural depicts reality rather than myth, the formation of suspended coffin burials and cliff tombs should be explained as follows: Long ago, a certain tribe (since this great tree differs from the one on the silk manuscript, I cannot confirm if this tribe was an early Tujia group) lived in the trees for reasons unknown. This existence encompassed all aspects of life—birth, old age, sickness, and death—forming a typical primitive tribal society. Driven by ancestral worship (or perhaps simply for burial convenience?), they exploited the ease of living in the tree: cutting branches, hollowing them into coffins, and then using the branches as pathways to carry the deceased to the cliff-side caves (which might have been natural formations or man-made excavations) or placing them directly on protruding rocks along the sheer face. If there were no caves or protrusions, they likely drove wooden stakes into the crevices of the cliff wall and rested the coffin upon them, creating a suspended burial.

This hypothesis resolves at least two issues: first, it explains why most suspended coffins are carved from a single, entire branch; and second, it explains how people with primitive productivity managed to place heavy coffins on sheer cliffs. In retrospect, it was simple: they accomplished feats modern people deem monumental by fully leveraging the advantages provided by their living environment, using a single giant tree to complete every step.

The height of the tree solved the problem of placing the coffins at the required altitude; the abundance of branches solved the difficulty of creating access routes and provided the source material for the coffins. This, then, is the answer to the mystery of the suspended coffins.

So, why are most suspended coffins found on cliffs overlooking rivers? This question is also straightforward. Firstly, water is the source of life, and the tree-dwelling humans would have required vast amounts of it for survival and procreation; the river provided this solution. Secondly, in ancient times, floods were likely their greatest natural fear, and tales of great deluges have circulated since the dawn of humanity, extending beyond the Huaxia people. Therefore, living high up in a great tree near a river and mountain was a brilliant survival strategy devised by the ancients. At least the early Tujia people in the Xi Du region must have inhabited such environments, as their stilt houses—diaojiaolou—still retain traces of this history!

Now, one final question remains: Where are the colossal, sky-touching trees of antiquity? Did such massive trees truly exist? This is hardly a question at all. According to my grandfather, when he was young, our Xi Du region was still largely deep, old-growth forest, teeming with towering trees, all later felled for charcoal or steel production. Not going back too far, the Fuqi Shan (Husband and Wife Fir trees) in the Tangya Tusi official city, which are only four hundred-plus years old, are already so immense. Had the ancient trees not been harvested by humans, in the four-season, abundantly rainy environment of Xi Du, it would have been easy for various trees to grow into giants.

Of course, as ancient people reproduced generation after generation, they could not remain living in the trees forever. Life centered on the tree and life in the cave were merely historical phases; people eventually returned to the ground. Logically, human reproduction did not cease, but why did the practice of suspended coffin burial vanish after a certain period? I believe the fundamental reason is that people no longer depended on the great trees for their livelihood. Having returned to the ground, practicing suspended burial became immensely troublesome. Thus, for the Xi Du area, the primary mode of burial shifted to interment in the earth, which reflects the process of funerary customs changing in tandem with shifts in the living environment.

At this moment, I vaguely recall that the Suoluo Divine Tree depicted on the silk manuscript also seemed to show a burial scene. However, at that time, my entire focus was on deciphering the Blood Soul Stele, and the burial scene in the drawing was not prominent, so I paid it no mind. Now, comparing it with this mural, the burial scene on the Suoluo Divine Tree has snapped into sharp, startling focus.

I habitually patted my back, only to find emptiness. My backpack was gone. Startled, I quickly asked Tan Ping'er, "Where's my bag?"

"You left it at Elanguo's place when we were eating yesterday!"

I breathed a sigh of relief and patted my chest. As long as I hadn't lost it in this sunless place, that was what mattered. For Ji Ye and Man Niao Niao, even though Tan Ping'er and I are now neither seen nor heard from, they would certainly take my belongings; that much was certain.

The Blood Soul Stele, the two ceramic seals, and that silk manuscript were all in my backpack!

I explained my theory about the suspended coffin burials to Tan Ping'er. She nodded. "Looking at this mural, the secret of the suspended coffins only makes sense if it's as you say."

"Yes. Because I'm a local, I've been hearing bits of local customs and legends from the old folks since childhood. Now, comparing what I heard with this mural, I suddenly realized that some seemingly mysterious phenomena actually stem from daily life or the survival environment of that time. If you don't understand the root cause, you can't solve the riddles left by the ancients."

"Then," Tan Ping'er's playful voice was pleasant in the darkness, "let's go out and find some people to look at this later. Maybe you'll make history!"

I managed a wry smile. "It's a pity this great tree on the mural isn't the Suoluo tree we're looking for. What good is solving the age-old mystery of suspended coffins? All I want now is to find that Suoluo tree quickly. No matter the outcome, I never want to crawl through the earth or climb into the sky to these places where even ghosts detour."

"Ying Ying," Tan Ping'er murmured in the darkness after a moment, "Look. According to you, suspended coffin burials only exist in mountainous regions, and Xi Du is also full of towering mountains. Even though the tree here on the mural might not be the Suoluo tree we seek, think about it: based on the records on the silk manuscript, even if the tree species is different, isn't the scene of human life very similar?"

"Well... I already knew that! What exactly are you trying to say?"

"Idiot!" In the darkness, Tan Ping'er accurately tapped my forehead. "The silk manuscript doesn't have the two mountains shown in this mural because the focus of the original illustrator was different. Now that we see this mural, can't we boldly predict that there should also be suspended coffin burials near that Suoluo Divine Tree?"

"That's right!" I felt a jolt of sudden enlightenment. How could I have missed such a simple, obvious clue? My face flushed, but I stubbornly retorted, "I was so focused on the suspended coffins just now that I didn't think of that angle for a moment!"

The darkness remained heavy, but my mind was suddenly crystal clear. Though I couldn't see what was before me, a vivid image formed clearly in my head: giant tree, river, sheer cliff, ancient people, suspended coffins... Apart from the dazzling brilliance of the suspended coffins, everything else instantly faded to black and white, blurring and receding.

"Let's go, we're heading back to the suspended coffins right now!" I lit a torch and pulled Tan Ping'er to go back.

"What are you doing?" Tan Ping'er snatched her hand away. "There are suspended coffins where we fell from, but there wasn't any great tree nearby. Besides, think about it—this mural clearly depicts a scene of human life; how could they hide in gloomy, dark underground caves?"

"Then what's your point?"

"We keep moving forward. Once we find the exit, we can try to inquire around to see which other places in Xi Du have suspended coffins. Following up on that lead will be much better than you wandering around aimlessly, relying on fate!" Tan Ping'er had actually picked up the local dialect word for 'relying on fate' (xintian guri), and her reasoning was so sound that I felt returning to the suspended coffins we just left would be pointless—in terms of timing, location, or human resources, it was like throwing a meat bun to a dog.

Furthermore, Tan Ping'er was absolutely right. Although the ancient Tujia people had a period of cave dwelling, they couldn't have lived entirely without sunlight. And a tree cannot grow where the sun never shines. As for the suspended coffins in Yumu Cave, it's highly likely, as the experts suggested, that they were lowered from above.

We quickly packed up, abandoning the white fish, called out to Hua'er, and prepared to move forward. To conserve torches, we lit a piece of fir bark, threw it a good distance ahead, and used the time it burned in mid-air to get a clear look at the path. If it was flat ground, we would sprint quickly to the still-burning torch, grab it, and reuse it. If the path was rougher, we would follow the rock wall.

This method saved both time and fire source, allowing us to advance much faster.