Because it was a close-range attack, two of the poisoned blowgun darts pierced directly into the eyes of the Deinosuchus. After only a brief struggle, the Deinosuchus immediately went limp.

Such a large dose of anesthetic was applied so close to the brain. Even a behemoth like it couldn't withstand it and immediately fell unconscious.

Now that the Deinosuchus has climbed ashore on its own, we don't have to go through the trouble of dragging it out of the water. This Deinosuchus is fully grown, with a body length of over twelve meters and an estimated weight of at least two and a half to three tons.

They were making a killing before, and now they're making money like crazy!

This fish, weighing over ten kilograms, has increased in value four hundredfold. If those fishing veterans saw this, they would probably be envious for over a decade and it would be talked about for decades to come.

A sustainable path has emerged before us, and we should make better use of this means of obtaining food.

I asked everyone to dig two ditches, each ten centimeters deep and fifty centimeters wide, from the water channel to the riverbank, connecting the land near the waterwheel on the riverbank.

In this way, excess water in the irrigation ditch can flow back into the main river through these two ditches near the riverbank, preventing water from overflowing into their camp.

This separated land will not only better protect the waterwheel for future maintenance, but it will also make it much easier for us to go fishing and find food.

Two more days passed, and by then we could see the Prosopa spp. spreading toward us.

We were less than a hundred meters away from the ditch we had dug. Watching the trees and weeds in front of us being gradually eroded and destroyed by white mycelium was still a very thrilling experience.

We've stocked up on quite a bit of meat over the past two days, mainly fish and crocodiles.

I had seen those lake monsters before, but two days have passed and we haven't caught any of these strange animals.

I don't know if they're smarter and don't come here or what, but my wish to see these animals that almost killed me and Top again is temporarily dashed.

All the ditches have exceeded their targets. Not only has their width been increased to one meter by the newly arrived Haru army, but it is actually much wider, estimated to be one and a half meters wide.

It was three times wider than previously estimated, and the depth was also increased to one meter.

Haru was just bored and felt it wasn't right to just sit around doing nothing, so he took the initiative to dig it up himself.

The depth and width of this canal are almost comparable to a medium-flow stream, so there's no need to worry about drinking water at all.

The *Prosopa spp.* grows very quickly; it covers a distance of 100 meters in just one hour. The trees and weeds are then completely covered and decomposed by the white mycelium.

Afterwards, the mycelium burrows back into the soil and begins preparing for the root system of the fruiting body to take root.

After all, those tall Procyonoides fruiting bodies also need to absorb oxygen and participate in the release of carbon dioxide.

We could feel that the altitude sickness had become more and more pronounced in the last few days. Fortunately, our bodies gradually adapted, so none of the tribe members experienced much discomfort.

However, the work cannot be as strenuous as before, and the lungs need some time to fully adapt to this low-oxygen environment.

However, in the context of widespread oxygen deficiency on land, some aquatic plants that were originally inconspicuous in the water have begun to grow wildly in this high carbon dioxide environment.

The most prominent examples are snapdragons and some silk grasses in the water. They are very sensitive to changes in the carbon dioxide concentration in the environment, and they will grow wildly as soon as the concentration is high.

There is another type that reproduces even faster than these aquatic plants, and that is duckweed.

Unlike aquatic plants, duckweed can directly utilize carbon dioxide from the air and release oxygen through photosynthesis.

In the past few days, the water surface has been covered with duckweed, and the thick layer of duckweed has become food for many herbivorous fish.

While the land was eerily silent, the water, ironically, flourished and thrived.

No fish has ever been able to feast on food as freely as they can now, with so much food they can't possibly eat it all!

Since the main source of oxygen is in the water, it is actually more comfortable to stay by the water than on land.

This further strengthened our resolve to build the Ark.

Some broaching saw blades have already been produced. After a series of quenching treatments, the saw blades have become very hard and are estimated to be comparable to industrially produced products.

The two-person teams began logging on the three mountains. Cutting down the trees would undoubtedly make the oxygen on land even thinner.

However, we have no choice but to cut down trees; the Ark will definitely require a large amount of wood to take shape and be built.

However, the problem of oxygen deficiency also needs to be solved, otherwise the efficiency of logging will be greatly reduced, and the tribesmen will not be able to hold on for long before they become dizzy and lightheaded due to lack of oxygen.

There was no other way, so I had to take some time again to make a gearbox out of wood.

The waterwheel now has a large torque. By adding a gear to its main shaft, and then using a gearbox that changes speed several times, the driven shaft on the other side will rotate at a very high speed.

Below the gearbox is a stone platform more than a meter high, built of stones, which facilitates the routine maintenance of these parts.

We spent an afternoon making a six-winged propeller fan out of a felled balsa wood.

This type of balsa wood is very lightweight and strong. It is generally used as a consumable material in aerospace and wind power generation projects.

The finished fan is 1.5 meters in diameter, but weighs very little, less than 5 kilograms. The driven shaft of the gearbox can drive the fan to rotate at high speed.

The fan is positioned directly near our campsite, and the strong winds blowing through it can carry heavier carbon dioxide away from our campsite.

After the air is circulated, the proportion of carbon dioxide will be greatly reduced. When people are working, not only will the temperature be lowered, but breathing will also be much easier.

Since it is entirely water-powered, there is no need to consider energy consumption. As long as the river continues to flow, the power will be continuously converted into usable energy through the waterwheel.

To better utilize the power of the waterwheel to its limit, I separated the driven shaft of the gearbox using gears and connected it to the ground via a linkage device.

This part requires very little power and will not affect the operation of the fan.

Using the power from the ground, I directly took a rough whetstone, hammered it carefully, and polished it into a regular round shape.

Using a compass made of a tree branch, the center point of the circle was marked, and a square hole was carefully chiseled out. After being mounted on the prepared frame and connected to the drive shaft, an automatic polisher was hand-rubbed out.