48 Hours a Day

Chapter 904: Underwater Ruins

It was June, and the sunlight was still reasonably sufficient. The three felt a little stuffy in their wetsuits, but the stuffiness somehow disappeared the moment they entered the sea. As they dived deeper into the ocean, the temperature around them began to drop as well.

With a much higher thermal conductivity than air, a human would lose more heat in the water than on land. Fortunately, their diving suits helped them fight off the cold. Usually, casual divers like them would not dive too deep into the sea. Every ten meters deeper, the pressure would turn up a notch. After diving deeper than thirty meters, they risked suffering from nitrogen intoxication. The ordinary diving cylinder would typically be filled with compressed air consisting of 21% oxygen and 79% nitrogen. Under high pressure, nitrogen would enter the diver's body, and at the same time, breathing pure oxygen under a high-pressure environment for too long would cause oxygen poisoning.

The undersea ruins that Zhang Heng and the others were about to explore this time were probably located at a depth of about 25 meters. Diving to such depths was usually not risky, and with Zhang Heng's swimming and diving skills he had honed in the Black Sail dungeon, he could dive to this depth in a single breath without any diving equipment. However, he would not be able to stay underwater for too long, still needing to emerge to catch a breath after taking a glance at the ruins.

Strictly speaking, this was not Zhang Heng's first dive. When he was a child, he followed his parents to see corals in Sanya. It was a purely parent-child leisure activity, though, where the dive depth was less than eight meters. The time he spent underwater was also very short, which was only twenty minutes. Throughout the entire diving experience, he was accompanied by a coach.

Zhang Heng's only long-duration dive with diving equipment was when he entered the Apollo training camp. NASA had made use of an underwater environment to simulate a zero-gravity environment. Not only did Zhang Heng have to stay underwater for a long period, but he was required to complete a series of given tasks.

Hence, Zhang Heng did not feel unfamiliar when he went underwater again.

Whether it was the zero-gravity environment or the quietness, the seawater almost isolated all the noise. In the midst of a dive, each diver could only hear their own breathing, especially during exhalation, where the sound of the bubbles exiting the tube could be somewhat relaxing.

Nellie behaved very professionally. She would stay no more than two meters away from her clients throughout the entire dive, paying close attention to their physical and mental conditions. After confirming that they were encountering no troubles during the dive, she pointed to the ruins that weren't too far away and signaled them to follow her.

In fact, there was no need for her signaling. The moment they dived into the sea, it was difficult for them to ignore the sight in front of them. The ruins appeared to be a vast underwater palace taking the shape of a pyramid. With a rotting, decrepit exterior, the structure was said to date back to about 10,000 BC.

If these ruins were built by the people who lived here, they might have mastered the building techniques the Egyptians possessed when building the pyramids. However, the Egyptians had only started building their first pyramid around the third millennium BC.

This was why many experts firmly believed that the stone structure in front of them was simply a masterpiece of nature. After witnessing the well-aligned stone steps and the smooth and square stone wall, however, Han Lu was more inclined to believe that a mysterious lost civilization must've left them behind.

She even spotted some structures that looked like gates and roads. Nellie then gestured to Zhang Heng and Han Lu to get closer to the ruins while she picked up the underwater camera to take a photo of them with the ruins in the background. After that, they swam towards the gate.

Han Lu followed Nellie with her video recorder, while Zhang Heng looked at the time and direction on the dive computer and followed them. The three soon passed the stone gates.

These structures were supposed to serve as the city gates, but they turned out to be made of giant stones stacked together. Schools of tropical fishes of all manner of color scooted around them. Zhang Heng Heng even saw a tiny sea hare.

As its name suggested, this sea creature appeared as cute as a little rabbit with ears, though it did not mean that there were no ugly sea hares. Not even an iron lady like Han Lu or a young girl like Nellie could resist such a cute creature; hence, they started snapping pictures wildly like a photographer shooting Victoria's Secret models on a runway.

In the end, they stayed there for about a minute before moving forward. After that, the three of them swam through a narrow spot. Only two people could fit side by side in the narrowest spot in the ruins. Once they swam through that, their vision suddenly widened, as though they had entered to an underwater palace.

They saw walls made of rocks and the seawater above them reflecting the sunlight when they looked around. Nellie, who led the way in the front, stopped moving, put her left and right hands together, and quickly moved her thumb up and down. She was trying to tell them that there were turtles in front of them. Han Lu then swam towards Nellie, and that was when she saw two turtles between the stones. So, she too signaled Zhang Heng behind to come over quickly.

However, it seemed Zhang Heng was lost in his thoughts and did not see Han Lu beckoning at him. For some reason, when he first saw the underwater ruins, the feeling of dejà vu struck him. It wasn't too strong at first, but the feeling resurfaced when he arrived at this huge open space. And this time, Zhang Heng knew where his dejà vu came from.

He had a weird dream in the alien quest before. In the dream, he came to a seaside town with a gloomy atmosphere. After he gathered the Shadow Sets, he returned to that seaside town again. He was feeling right now as when he traveled back to the seaside town for the second time.

Considering what happened later in that small town, this was not a good sign.

Being a well-known diving spot that welcomed throngs of tourists each year, there were no recorded accidents here so far. Still, Zhang Heng did not want to doubt his instinct.

After that, he decisively gave Han Lu and Nellie a thumbs up to tell them that he wanted to surface. Nellie felt a little strange, not knowing why Zhang Heng wanted to go up so suddenly. She then gestured to him, asking what difficulty he might be encountering. Han Lu, on the other hand, was more experienced in dealing with a situation like this. She and Zhang Heng had experienced the death dream together, and after that incident, she trusted him unconditionally. She also knew that there was a crazy and dark world beneath the ordinary one.

Therefore, upon seeing this, she did not question why Zhang Heng made such a decision. Instead, she quickly made an upward gesture as well. However, they saw that Nellie's face had suddenly changed, and she was anxiously making a downward gesture.