The time spent in the cave was longer than Renault expected, because from the evening of the third day, a medium-sized storm came to more than half of the bay sea, turning the sea into a dead sea full of rough waves.

In terms of time, Odin and Haichao should have sent the first "former" slaves to Midway Island and are now on their way back to Kulun island.

There is no need to worry about the safety of the fleet. With the "walking weather satellite", the fleet can go to the shelter to avoid the storm.

Everything has its advantages and disadvantages. On the one hand, the storm delayed the journey of the fleet, on the other hand, it also blocked the search of the black orcs.

From the fourth day on, Renault did not even see the shadow of the devil''s eye when he strolled around the island of Kulun. It was obvious that their flying mounts could not withstand such a violent storm.

If it''s just a storm, those big birds can stick to it, maybe it''s easier, because the storm means more and stronger air currents. Big birds can fly with the help of air currents, and they can hover in the sky for 1 or 2 hours without waving their wings.

But the main cause of the storm is the cold current coming from the south of the polar region. If there is a lot of water vapor in the atmosphere, the cold current will sweep out and bring a snowstorm. If the air is dry, there will be only a storm.

In either case, the temperature is bound to drop sharply, and it''s just a matter of time before it''s more than ten degrees below zero.

When flying in a low temperature and strong wind environment, the heat will be lost very quickly. For big birds, this is dangerous. Once their body temperature drops to a certain level, they will lose control of their wings. Maybe they will fall into the sea and be drowned alive.

Renault conjectured that the storm was probably only part of the reason why the search efforts of the black orcs were greatly reduced, and the other part was due to the lack of harvest for a long time.

After a long search, no hair was found. The black bastards are not idiots. They know that the longer the time goes by, the less likely they are to find the enemy. Of course, they are not willing to waste manpower and material resources.

But whether the eye comes or not, and whether the storm comes or not, it has no effect on Renault.

Anyway, when he went out for a walk, he always swayed under the water. No matter how good his eyes were, he could not penetrate the sea more than 10 meters deep. No matter how strong the storm was, the water was still calm.

Due to too much time to go to the sea every day, Renault has also created a good thing in his spare time to facilitate diving.

It''s a diving air bottle.

Although Renault''s physique is infinitely close to that of the awakened in the process of continuous magic power training, he can only hold his breath and dive for 12 minutes.

This data is very powerful on the earth. It''s more than enough to hang people all over the world, but it''s not a big deal in the alien world. Some people with extraordinary water systems can stay up for an hour or two.

They even have the skill of using extraordinary force to get oxygen out of the sea. It''s not a big problem to soak in the sea for a few days or nights.

In order to have more fun, Renault has other ideas to extend the diving time by other means.

Otherwise, it will float up once a while, which not only increases the probability of being found by the magic eye, but also makes it as unpleasant as the prostate patients who have to go to the toilet once a while.

is more critical, he learned magic energy black technology so long, can develop some Rune equipment, for Mao to be like idiot woodlouse, like suffocating, uncomfortable, not uncomfortable?

Of course not!

So Renault decided that Ben would never hold his breath.

Naturally, the idea of making "diving air bottle" came to his mind.

Over the past few months, a large number of magic black technologies have been developed in the territory. The pre technology for manufacturing diving air bottles has basically been lit up. It is only a matter of course to roll out diving air bottles.

The air storage structure of the air bottle can completely duplicate the high-pressure air storage tank on the high-pressure air gun, so that it can automatically inflate air. After using up the activation Rune disk, it can inflate air on the spot, which is convenient for a batch.

However, the high-pressure air is stored in the air bottle. If you breathe this thing directly, you will be killed. So you need a pressure reducing valve to convert the high-pressure air into normal pressure air.

The principle of the pressure reducing valve is also very simple. A piston cylinder installed with an internal spring is done, and Renault can roll one out every minute.

From making the decision to rolling out the first diving air bottle, Renault only took three hours, which is extremely efficient.

The internal pressure of the air bottle is 80 atmospheres. The gas stored in the air bottle can breathe underwater for at least 4 hours, which perfectly meets the requirements of conventional diving.

It''s just a little heavy, as high as 15 kg, which is very heavy for people on earth, but it''s nothing for people of other worlds. Besides, the environment is underwater, and the buoyancy of sea water can also reduce part of the weight.

Four hours of diving time is also enough to use, because after four hours of diving, the physical consumption of normal people has been great, if the time is longer, in case of physical exhaustion, it is very likely that there will be casualties.

Renault was also very satisfied with the test results of the diving air bottle. He carried the air bottle on his back and swam in the sea for more than two hours. He touched hundreds of conches and seashells on the bottom of the sea, with a total weight of dozens of tons. During this period, he did not surface once.When Renault used "mind power" to hold a conch and seashell piled up into a hill and ring the door of the cave, everyone was startled.

During the trial of the air bottle, Renault also came up with a new idea: can we develop a special diving power device?

Equipped with an air bottle, I can dive at least 500 kilometers in the water at one go. As long as I float up several times, I can cross the Pacific Ocean alone.

The width of the Pacific in the east-west direction is less than 20000 km. With Reynolds''s abnormal swimming speed of more than 150 kmh, you can swim across the Pacific in a week at most.

But this is only limited to him. Ordinary people don''t have this ability. Even the best water fisherman can swim 30 kilometers with a diving air bottle on his back, even less than a fraction of Renault''s.

So, is it possible to improve the speed of ordinary people?

The answer, of course, is yes!

And the solution is ready - made - water pump!

Magic pumps are available. Isn''t magic pumps a piece of cake? Isn''t it OK for the blade to turn in reverse?

As a result, after Renault worked hard for half a day, the diving air bottle changed into a "magic underwater propeller".

Two small magic water jet pumps were integrated on the air bottle, and another equipment with "epoch-making significance" was born.

Magic underwater propulsion is very important.

It''s no longer a hard job to dive underwater to collect conches and seashells, or to collect all kinds of algae. With the physique of people from other countries, it''s easy to dive 1 or 200 meters deep, and you don''t have to worry about decompression sickness and other messy things.

More importantly, it can also be used in the military.

For example, a special combat team equipped with magic underwater thrusters can perform various tasks from underwater, such as penetrating enemy ports, destroying enemy ships, and shooting enemies from underwater.

Anyway, the magic air gun is not afraid of water, so the special combat team can carry out the task with the air gun.

From this point of view, magic underwater propulsor must be listed as control equipment, not allowed to export.

After rolling out the first underwater thruster, Renault called for several island guards to test it.

In the face of the Lord''s command, these strong men did not hesitate to take off into bare pigs, put on the underwater thruster, and jumped into the icy sea.

Renault was quite satisfied with the results of the test. The island guards didn''t have to do anything, and the swimming speed easily exceeded 20 kmh.

They also made two suggestions carefully.

The first is, it''s too cold. After swimming for 20 minutes, my hands and feet are frozen unconscious.

Renault just turned his lips and ignored them.

This is not nonsense. As long as it''s not dead, we all know that the water temperature in the cold winter month is very low.

It''s because it''s very cold that I specially called you Island guards to come and test.

In essence, the island protection team is the professional army of the territory. In fact, the members are soldiers. When they fight, do they stop fighting because they are cold?

I''ll let you go in the water. I''ll give you a piece of wool.

What''s more, my master has said in advance that if I can''t carry it, I will come up quickly.

Second, because the speed is too fast, the oncoming water is too strong to open your eyes

This suggestion is very valuable, which indicates that the use of underwater thrusters must be equipped with "goggles", or diving helmet with goggles.

This one also inspired Renault.

In addition to goggles, divers should also be equipped with a thick "tight diving suit", which can be directly made of NIMA glue. On the one hand, it can keep warm, on the other hand, it can protect the body, so as to avoid injury caused by hitting the reef on the seabed.

In addition, wearing tight diving suits can also improve swimming speed, although not much.

Because the skin of the human body is very thin and the muscle tissue is relatively soft, under the action of water pressure, the muscle tissue will continue to deform and increase the flow resistance.

But NIMA gel diving suit is not the same, its toughness is good, strength is also good, easily will not deform.

Dolphins, seals, whales and other marine mammals on earth all have thick skin, which is precisely because of this reason.

However, there is no need for Renault to worry about diving helmets and diving suits. Just leave them to the rune Institute and let them design and manufacture them.

The storm lasted for three days before it began to weaken. At noon on the eighth day when she lived on Kulun Island, the figures of Odin and Haichao finally appeared on the distant sea level.

When the news was spread to the cave, the warm cheers broke out in an instant.

Even more than 900 "former" slaves are no exception,

it''s time to go home.