At this time, he was still rushing in the subway tunnel.
Because along the way, Fang Yu's prestige had been quietly increasing, and with Chang Shan's generous teachings, Fang Yu quickly mastered the skills of walking in the subway, and combined with the miscellaneous survival knowledge in his mind,
In just half a day, Fang Yu successfully obtained the actual leadership of the team.
Chang Shan didn't complain at all and directly retreated to the second line.
For Chang Shan, the mission is the most important thing during this trip. In addition, in the army, the most capable people always come first. A captain who is traveling temporarily is a very competitive person.
Fang Yu was walking in the front, holding a torch. What seemed to others to be a dark tunnel was, in his eyes, a three-dimensional map, with an arrow pointing the direction in the dark passage very accurately.
Suddenly, just as Fang Yu was walking forward, Fang Yu felt the flame of the torch in her hand suddenly dim.
"Wait!"
Fang Yu's voice echoed in the tunnel, and the team members behind him stopped one after another.
Fang Yu looked at the torch in his hand seriously.
I saw that the original orange flame suddenly weakened a lot, and for some reason in the darkness, there was a seemingly non-existent cyan halo around the flame. This reaction was not very obvious, but because Fang Yu had been paying close attention to it,
, this reaction was also among his observations.
In Fang Yu's novice gift bag, survival knowledge includes not only the wilderness, but also various survival knowledge in various underground caves.
In my memory, torches are the most important resource when walking in underground passages or caves.
Not only do torches provide light and blind some light-avoiding animals that survive in the dark.
It is also because torches can be used to determine whether many places can be walked and whether there are risks.
If the fireworks are weak, it means that there is less air circulation and insufficient oxygen in this space, causing the flame to weaken. The smaller the flame, the scarcer the oxygen.
Through the derived knowledge of the flame color reaction principle of flame, it can be known that flames burn in air with different components, and the refracted flame colors are different.
Normal flames appear orange in oxygen, but when reacting with phosphine, they turn green or blue-white.
This is what used to be called ghost fire and ghost fire.
However, if you want the flame to change color as a whole, just the air content is not enough. Generally, the flame color reaction occurs when various powders or corresponding metal blocks are burned, and there will be an obvious reaction.
Relying on air alone will at best cause some weak spectral effects, that is, showing similar haloes of different colors.
This change is very subtle and can only be discovered by careful observation.
Fang Yu also discovered it through observation when the flames became weaker.
This shows that there is less oxygen in the air in the front channel, and there may be other toxic and harmful gases.
"There may be a turbid air area ahead. To prevent accidents, everyone wears gas masks. Because oxygen is scarce, everyone should keep their heads down as much as possible."
As soon as Fang Yu finished speaking, everyone behind him took out gas masks from their backpacks.
As a prop for air filtration, gas masks actually have a certain anti-virus effect, but at the same time, they also block the normal breathing of the human body.
Because the air must be filtered by the filter before it can be inhaled into the body, this actually hinders the absorption of oxygen.
Therefore, especially in this underground tunnel, the oxygen itself is not sufficient. Wearing a gas mask throughout the entire process will only cause hypoxia. It can only be worn when passing through a certain dangerous area.
This is also the correct way to use a gas mask.
Before Fang Yu, they usually didn't know to wear gas masks until someone felt dizzy from smelling it.
There have been many accidents that resulted in attrition due to this.
Now that Fang Yu has reminded them, they have indeed saved a lot of trouble along the way.
After putting on their masks, everyone bowed their heads slightly and followed Fang Yu forward.
Fang Yu could feel that the tunnel seemed to be going downwards. The further down it went, the weaker the flames became and the harder it became to breathe.
Fortunately, the flame did not go out, indicating that there was still enough oxygen.
Fang Yu tried to speed up her pace so that the people behind her could follow. They had to pass through this area quickly.
The dim light of the torch showed different haloes in the darkness, indicating that in addition to oxygen, there were many other elements in the air, and the content was quite high.
Fang Yu lowered his head and quickened his pace. He could tell by the feeling under his feet that he had reached the bottom of the passage, where breathing was most difficult and his heartbeat accelerated wildly due to lack of oxygen.
But Fang Yu could only keep calm and continue moving forward.
Fortunately, after reaching the bottom, Fang Yu felt that she was starting to climb within a short while.
The flames also slowly recovered from the faintness.
Oxygen is gradually increasing.
After reaching a certain position, the torch returned to its original flame size, and the color no longer had various haloes. Fang Yu led everyone for more than ten steps before letting everyone take off their masks.
After taking off the gas mask, everyone including Fang Yu was breathing frantically.
It was as if he was trying to suck back all the oxygen he had lost before.
After everyone calmed down in place for about four or five minutes, they continued on their way.
But this time, after walking for another ten minutes, everyone arrived at the first stop.
For this route planning, although the straight line on the map shows only a dozen kilometers of road, due to various twists and turns, the total length is actually about twenty kilometers.
Now they have been walking for half a day, nearly four hours, and have covered about ten kilometers.
Compared to walking on the snow on the surface, it is more than twice as fast.
If Fang Yu could walk on the subway before, he might have arrived a few days earlier, and he might not have even encountered the storm.
However, even if Fang Yu wanted to take the subway at that time, she couldn't.
Basically, most subway entrances are now covered with ice and snow.
Except for Ziyang Shelter, which can break the frozen ice in the subway and dig a hole from the ground to the surface, if others want to dig a hole outside, it will take a lot of energy and heat.
, not to mention there are huge risks.
All in all, according to the speed of Fang Yu and others, they could arrive at Union Hospital the next day.
The speed can be said to be very fast.
After traveling for a long time, although there were torches, everyone was actually still in darkness, so everyone was very nervous.
After arriving at the rest stop, everyone ran to the subway entrance above.
Although the subway entrance was covered with ice and snow, and the temperature was very low.
But at least here, you can still see a glimmer of light.
Everyone shivered and walked to the subway entrance to let the light from outside shine on themselves.
Although this is not sunlight, but the kind of light equivalent to a cloudy day, and there is a blizzard howling outside.
But even so, standing in the light, everyone seemed to have been saved, and their faces that were red from the cold under the masks were full of comfort.
Even if they are just forced to survive underground, everyone still yearns for the light.