"Isn't it good?" Nangong Muxue asked, "What did you find?"

"The walls of the corridor, the floor is dry, there is no water seepage, where do you say that such a high concentration of water vapor comes from?"

"Could it be that there is water inside the warehouse?"

"Yes...... Lu Chen smacked his lips, "If this is flooded, it is the best situation, and the other situation is that it is very dry, and there will be no out-of-the-ordinary trouble, but now, there is still water in it, this is the most troublesome situation......"

Listening to what Lu Chen said, Nangong Muxue couldn't help but ask, "Lu Chen, you've been talking for a long time, what's in it?"

"I don't know ......," Lu Chen said, "Let's ventilate first, and I'll know when I go down tomorrow." ”

……

At noon, the engineer in charge of studying the composition of the air sweated profusely and ran to Nangong Muxue to report that they had found highly toxic cyanide in the impurity dust, and this thing would kill if it was inhaled in a few puffs.

Nangong Muxue couldn't help but be afraid for a while, even if she wore a gas mask, this thing would be poisoned if it came into direct contact with the skin! But Lu Chen ...... He just went straight in!

With the analysis materials in hand, Nangong Muxue hurriedly ran to Lu Chen's side and said, "Lu Chen, you must receive treatment immediately!"

Lu Chen looked at the materials and waved his hand, "This toxin doesn't work for me......"

"You...... Are you really okay?"

"It's okay......" Lu Chen said, "Cyanide...... I guess some biochemical materials have leaked, so when you go down, put on a biochemical suit. The sachet is placed on the outside of the biochemical suit!"

Nangong Muxue nodded, there are only seven sets of biochemical suits, and there are even fewer people who can go down. But...... To be on the safe side, this can only be the case.

……

The next morning, the engineer in charge of acousto-optic monitoring information found Nangong Muxue with the data analysis results, and seeing his strange face, Nangong Muxue asked, "What's the matter?"

"The photoelectric monitoring didn't find anything, in terms of sound, the first half of the night was fine, and the second half of the night was ......," the engineer lowered his voice, "There are a lot of signals in the ultrasonic spectrum, you see...... We did a preliminary analysis, and it was some regular signals, but I didn't know what that meant. You see, this waveform is repeated four times, with the same interval each time. This complex waveform was repeated six times, and each time it was the same...... And this...... This is the result of modulation, which is a mixed signal, and the spectral composition is very complex. And this...... This signal is repeated the most, but at different intervals. ”

Nangong Muxue looked at the printed waveform chart, pondered for a while, and said, "Can you use signal processing methods to modulate the range that the human ear hears?"

Yes, I've done it, you listen, it's interesting.

The engineer said as he turned on an audio device, and after a while, a voice was heard.

The sound is somewhat like the chirping of birds, some like the bursting of bubbles in the water, but the most peculiar is the sound of a train horn.

"Can the source of these sounds be determined?" Nangong Muxue asked, "Could it be the sound of the air flow of the blower?"

"I've removed the sound component of the blower. "According to my analysis, these sounds are very similar to some kind of animal, and the audio material I passed by in the primeval jungle is somewhat similar to the results of this spectral analysis. ”

"You mean there's life in the warehouse?"

"It's just a possibility, or the sound of the air flow as it passes through the complex terrain inside, I can't be sure yet. ”

Nangong Muxue nodded, "It seems that not only do you have to wear biochemical suits, but you also have to bring more weapons and ammunition." ”

When it was time to set off, including Nangong Muxue and Lu Chen, seven strange-looking people in biochemical suits stood at the entrance of the gate.

Lu Chen didn't really want to wear this thing, but in front of so many people, he didn't want to be too special.

The biochemical suit has a battery and provides wireless communication, which can ensure one-to-one and one-to-many communication between seven people.

On the public channel, all I heard were complaints about biochemical suits.

"This thing is too heavy!"

"Is it really necessary?"

"Is a gas mask enough?"

"In order to prevent panic, I haven't told you about the test results of the air composition yesterday," Nangong Muxue's cold voice sounded, "The air inside contains a small amount of cyanide, although it has been ventilated, I don't know if it has been replaced, and moreover, cyanide may come from the leakage of biochemical items, and now I don't know if there are other leaked things, if anyone feels that the biochemical suit is inconvenient, they can take it off now, stay on it, and change someone!"

At this time, no one spoke, and everyone quickly closed their mouths and said that "they will definitely be able to overcome the heavy difficulties of biochemical suits".

Lu Chen couldn't help but laugh when he heard it, it seemed that Nangong Muxue's girl was still very prestigious in Seven Zero Four.

……

With Nangong Muxue's order, seven people like robots slowly walked into the passage under the warehouse.

Lu Chen walked in the front, followed by Nangong Muxue, and the other five warriors followed in turn. All of them were armed, so to speak, fully armed. In order to make it easier to communicate, after going down, everyone's pronoun is the channel number of communication. Lu Chen is number zero, Nangong Muxue is number one, and the second to seventh are behind.

After walking along a step for more than ten meters, it was a turn, and Lu Chen turned back when he arrived here yesterday. Mochida Asuka's map does not show such a corridor, and the maze shown on the map has four entrances and exits, and I don't know which entrance and exit this corridor corresponds to.

According to Lu Chen's judgment, the underground warehouse may not even be on the first floor of the labyrinth, but on several floors.

After turning a corner, the road became darker and darker, and Number Two threw a glow stick into it, illuminating the way, and there was a sign in front of it indicating that there was an elevator and a staircase.

Lu Chen smiled, "There is even an elevator, it seems that the project in this place is not small." ”

Everyone advanced to the elevator door, and No. 3 checked it for a moment and said, "It's an old-fashioned elevator, it should be for transporting goods, but now there is no electricity." I suspect there should be a generator underneath. ”

"Take the stairs. Nangong Muxue waved her hand, and the group opened the door of the stairs next to them.

The so-called staircase is the kind of spiral metal staircase, which has been exposed to this high humidity air for decades and has not been maintained, and has been corroded very badly, and the beams can no longer stand people, and only a circle of frames composed of crude steel pipes can still bear load.

No. 2 threw a glow stick at the bottom of the stairs, and in the clanging collision, the glow stick stuck more than ten meters below.