The 51st Division became famous, and the people sent a lot, and when they heard that they needed building materials, they went home to look around, but if they didn't have them, they dismantled their own door panels and wooden beams.

Some factories were already shut down, so workers were mobilized to dismantle the factories and pull truckloads of building materials to the front line, of course, these cars were also driven at night and could not turn on the lights.

Fortunately, most of the drivers are locals, familiar with the road, walk for a while and stop for a while, try to avoid the reconnaissance of the Japanese army, and can still transport a lot of things back and forth in one night.

Sangou received so many materials, plus the expertise and tools of the sapper platoon, they immediately excavated the hill according to Sangou's wishes.

Time was really pressing, and it was just shelled by the Japanese army in the morning, and after a while, the Japanese observation balloon flew like a ghost again.

This nasty balloon flies neither high nor short, the guns of the national army can't hit it, and the people above can observe the situation on the ground, this thing, only an airplane can handle it.

However, at present, the planes of the national army are fighting to the death with the planes of the Japanese army hundreds of miles away from the battlefield, and the air power is not only inferior to that of the Japanese army, but also very disparity, and the army naturally cannot rely on them.

As soon as the Japanese balloon arrived, everyone had to quickly hide it and not let it see it, otherwise, it would soon attract an artillery bombardment, or even a strafing fire from enemy planes.

In the early days of the War of Resistance Against Japanese Aggression, the Military Command Department repeatedly strictly ordered that no army unit fighting on the front line should use rifles and machine guns to attack enemy planes without air defense forces.

What kind of bullshit order and regulation is this, the troops on the front line are so angry that they have to be wreaked havoc by enemy planes, and sometimes, you can see the Japanese pilots in the arrogant enemy planes, but they can't fight, it's really infuriating.

Sangou didn't understand it at first, but then he heard Niu Gu say that this is also a last resort, how can you beat the plane down with a few broken guns of an infantryman, and you haven't learned how to fight anti-aircraft machine guns and anti-aircraft guns.

If you shoot, not only will you not even be able to hit a single hair of the Japanese plane, but you will expose your hidden position, which will definitely cause the enemy plane to turn around and attack.

Once you provoke the Japanese pilots, even if you suffer yourself, it will also affect other brothers who are in the same position as you, and people will fly over, just a strafing shot is enough for you to eat a pot, not to mention that there are many bombs on other planes.

Therefore, the three dogs they could only play hide and seek with the Japanese soldiers overhead, flew in, hid, left, quickly got up and dug a few times, according to this progress, it is estimated that after a few weeks, the excavation of the tunnel may not be completed.

What to do? ……

What to do? Cold. Brothers of the engineering unit, pay attention to the three dogs, don't you have some explosives in your original ammunition depot (hole).

You can make a fuss about these explosives, their sappers have technology and experience, and they can match the amount of explosives for digging some holes, and Sangou immediately agreed, so that the speed of digging holes is much faster.

Compared with the cement steel frame, there will be a little more wood, which will be used as a support frame, but there is too much groundwater here, and the wood will quickly soften and rot, and some stone is needed.

Not far away, there is a large piece of creek beach stone, in this place, it is indeed rare, but it is still found for everyone, but there is a lack of tools for mining stone.

Niu Gu thought of a thief's solution, and in the afternoon, he asked someone to set off fireworks on the rocks of the stream, and sure enough, the Japanese soldiers took the bait, and a cannonball passed.

The artillery fire of the Japanese army blew up a large piece of river beach rock, blowing up a lot of stones and gravel, and at night, Sangou called people to smuggle it over.

The progress of this digging is a piece, and immediately there will be insufficient manpower, Lao Hu has a way, directly find the Shanghai Scouts who support them, a phone call over, and take advantage of the dark night, and pull several truckloads of construction workers to come.

Good fellow, under the guidance of the three dogs, they dug several holes separately, with the measurement and positioning of sappers, and in just one night's work, the hill bag was hollowed out, and the inside extended in all directions.

During the daytime the next day, the group of builders stayed behind and reinforced the interior of the cave with stones and wood, reinforced the entrance with cement and steel, and built the sewers.

The rocks of the stream were blown open, and the water level of the stream was lowered a little, and the three dogs told people to build the sewer all the way to the stream.

At the same time, two more trenches were dug in front of the original outer trenches, which were connected together, the water level was lowered, the drainage was solved, and all the trenches began to be dug deeper.

Grooves were made of stone at the bottom of the trenches and planks or strips were laid on top so that even if it rained or the groundwater came up, the water would flow down the grooved ditch to the lower level of the stream.

In addition, Sangou also asked people to bury some trick mines with grenades and make some alarm devices at the forward position outside the first line of positions overnight.

By the way, I also dug out some trap holes, and dug out vertical holes more than one foot deep with a large round shovel like the Luoyang shovel (the sappers specially asked the construction workers to find it for mountain positioning).

Some also brought old bamboo tubes to open and put them down in the vertical holes, which were camouflaged with some firewood and grass, which was very useful for dealing with the horse's feet of the cavalry, and the horses galloped quickly.

Once the foot falls into a deep vertical hole, it is not only the horse that loses its front hooves, but its own huge inertia, and the horse's feet will be broken if it can't stop with its body.

The hole of the hill bag is not straight in, similar to a T-shape, to avoid bullets and attacks, and the hole is camouflaged. Before the tunnel project was completed, Sangou took the brothers of the 7th Company to familiarize themselves with the terrain and dark passages, and everyone had to keep it in mind.

At every bend, some marks were made on the half-high wall with stones, otherwise in the dark tunnel without lights, no matter how familiar it was, once the war was tight and tense, everyone would be in a hurry.

Lao Li Tou is now a squad leader, and he has moved the cooking class in, and a small well has been dug deep in the tunnel, and the abundance of groundwater ensures that everyone has water to drink at any time.

……

It took two or three days for everyone to work hard to get this tunnel and the outer defensive position well, and it was also thanks to the Japanese army, and it is estimated that they were also transferring troops to punish the generals in the past two days, and did not come to attack, but only occasionally fired a few cannons to harass the position of the national army.

With the help of the local people, the comrades-in-arms did not interfere too much in the construction of the tunnel, but under the arrangement of the company commander Niu Gu, they devoted their energy to familiarizing themselves with and training the tactics of combining the tunnels of the three dogs with the defense of the position.

The 51st Division did not carry out night attacks for the time being, and most of them were taking advantage of the time to strengthen the fortifications; Fools know that the Japanese army has just suffered the loss of being attacked by night, and it must have been very well prepared.

……