Those small-looking 75-millimeter shells, after landing and exploding, are even more powerful than 120-millimeter caliber round howitzer shells.

And those 150 mm grenades have an even more amazing explosive power, and sometimes one of these shells can destroy an entire company's artillery position.

Even if the front line of defense is fortified, it is useless to hide in the trenches, and after these heavy shells fall, their huge explosion power is enough to directly shock the soldiers hiding in the trenches and anti-artillery holes.

Yuan Yonghan, who was supervising the battle on the front line, only watched the shelling of the South China Navy for ten minutes, and his face was like ashes, and after half an hour, he had already begun to prepare to send reinforcements forward.

But when he learned that the follow-up reinforcements had just been assembled, and they had not yet reached the front line, that is, when they were subjected to long-range artillery bombardment by the enemy and suffered heavy casualties, Yuan Yonghan no longer cared about any reinforcements, nor did he care about what to defend to the death.

Under such a fierce artillery bombardment by the South Navy, their defense line could not hold up at all, and even the infantry of the South China Navy did not need to come up, and their defense line could be smashed to pieces by artillery bombardment alone.

Therefore, an hour later, as soon as the South China Navy on the opposite side launched a large-scale infantry attack, Yuan Yonghan did not hesitate to order the whole army to retreat to avoid fighting the South China Sea in a positional battle.

Subsequently, all units should choose flexible mobile operations and adopt frequent small-scale battles to deal with them.

Since the artillery can't be compared, then don't let the opponent's artillery also play a role.

Fighting head-on, this almost allowed the opponent's artillery to play the maximum role.

However, if it is a mobile small-scale operation, then the artillery advantage of the Southern Navy is not so much, and the infantry of the Southern Navy cannot always advance with artillery every day.

Yuan Yonghan's decision was far more decisive and resolute than the other feudal towns that the Southern Navy had faced before, and the battle was only an hour away, and even when the large-scale infantry attack of the Southern Navy was still in its infancy, and many infantry units were still maneuvering and approaching, he directly chose to retreat with the whole army.

This change surprised the high-ranking generals of the Southern Navy, but it was also good to avoid wasting too much time and ammunition on the Hetai defense line.

And, they can run if they want?

How can it be so easy!

If they thought that they would be able to retreat successfully by retreating on their own initiative, they would not have taken the cavalry units of the Southern Navy into account.

The original Quyang Prefecture Second Army, the Ningyu Prefecture Eastern Expeditionary Force, they also wanted to retreat, but did they succeed?

No!

In the end, they were all intercepted by the cavalry units of the Southern Navy, and finally surrounded and annihilated!

As the enemy army took the initiative to retreat, the two cavalry corps in Nanhai Prefecture also began to attack!

The two cavalry corps began to advance rapidly from the north flank, and the cavalry troops, totaling more than 40,000, quickly advanced forward from the north flank like a flood of the embankment, and then circled in a semicircle, forming a huge left hook.

Once this left hook is successfully punched out by the Southern Navy, then at least more than 100,000 Yuan Yonghan's troops will be completely surrounded!

The reason why there are only 100,000 is because Yuan Yonghan is more cautious and adopts a multi-level defense system, and the front-line troops of the Hetai defense line on the front line are only 100,000, and there are many batches of strategic reserve troops behind.

At first, he thought that the front-line troops would rely on the fortifications to defend to the death, and then gradually reinforce them, striving to fight a war of attrition.

Even if the Hetai defense line is lost, then he will be able to organize his troops to build a second or even third line of defense later, and he will also be able to use space in exchange for time, adopt a gradual defense, pull into a supply line for the Southern Navy, and finally stabilize the battle line, so as not to say that the Hetai defense line will collapse and be completely finished.

However, he still underestimated the ability of the Southern Navy to attack fortifications, and the powerful artillery fire was not able to resist head-on at all.

Therefore, when he ordered the troops to retreat, Yuan Yonghan had actually given up the plan of frontal resistance of the second and third lines of defense, and instead planned to completely switch to mobile warfare, stretch and widen the battle line, and turn large-scale battles into small-scale battles.

He believes that in such a small-scale mobile operation, the powerful artillery strength of the South China Navy can be reduced to the greatest extent, and when only infantry or cavalry participate in the skirmish between the two sides, then the own side will not be at a huge disadvantage.

Honestly, Yuan Yonghan's idea is correct.

Compared with frontal positional warfare, it is indeed a mobile operation that can reduce the superiority of the South China Navy.

But this is premised on the fact that they can organize frequent, intensive, small-scale mobile operations, or they can only resist sporadically.

And there is another premise, that is, the South China Navy gives them this kind of opportunity!

But obviously, the Southern Navy has no intention of giving Yuan Yonghan this opportunity!

After discovering that Yuan Yonghan's troops had taken the initiative to retreat, Lin Ziran immediately ordered the two cavalry corps to launch a large-scale strategic detour according to the advice of the General Staff.

Trying to cut off the opponent's retreat, leaving them behind, and then annihilating.

Yuan Yonghan naturally won't sit still, he also has cavalry troops under his command!

When a large number of infantry units retreated, he also sent cavalry to take the initiative to intercept the roundabout cavalry units of the Southern Navy.

The cavalry units of the two sides met in the northeast direction of the Hetai defense line at noon that day, one side wanted to break through and make a strategic detour, and the other side wanted to stop them and cover the retreat of a large number of main forces.

In this case, a large-scale battle between the cavalry was inevitable!

However, what made the generals of the Dongdingzhou cavalry unit depressed was that the combat mode of the cavalry unit of the Southern Navy on the opposite side was different from the traditional cavalry combat mode.

Some of their cavalry units did not directly brandish their sabers to charge, but after riding horses and maneuvering in place, they directly dismounted and fought on foot, and more importantly, they even carried a large number of cavalry guns.

Damn, these cavalry guns turned out to be breech-loading rifled guns as well.

They turned a simple cavalry unit into a combat mode that combined infantry and artillery cavalry, so that after the fight, Yuan Yonghan's cavalry troops did not charge, nor did they not charge, and the fight was extremely awkward.

Song Youzhongqing, the commander of the First Cavalry Army and the commander of the cavalry roundabout troops, laughed when he rode on his horse and watched the other cavalry corps not yet charge, and was still in the midst of the assembly, when he was heavily shelled by his own cavalry artillery, resulting in heavy losses.

With the armament of rear-loading guns, even the tactics of cavalry units changed.

The opponent's cavalry troops, however, have not changed, and still hold the old cavalry tactics.

This wave, your own side is stable!

Sure enough, after the main cavalry forces of the two sides came into contact, the Dongdingzhou cavalry troops, which were already at a disadvantage in strength, were soon overwhelmed, unable to stop, unable to rush, and finally forced to retreat.

At this time, Song You personally led the cavalry troops to launch a large-scale counterattack, this time the counterattack was a traditional wall charge, and successfully defeated the enemy's main cavalry.

In this battle, 40,000 cavalry of the Southern Navy fought against about 20,000 cavalry of Dongdingzhou, and finally ended with more than 2,000 casualties of the cavalry of the South Navy, and nearly 10,000 casualties of the cavalry of Dongdingzhou.

The cavalry units of the Southern Navy have won a great victory!

And cleared the main interception force of the enemy's troops, gaining space to continue the detour.

In the evening of the same day, the cavalry corps led by Song You had successfully detoured back to its position and intercepted about 80,000 Yuan Yonghan's troops.

At this time in the battle, it was actually possible to declare the entire army of Yuan Yonghan's first line of defense troops annihilated.

In addition to the tens of thousands of cavalry and more than 10,000 infantry led by Yuan Yonghan himself successfully escaped from the encirclement, the remaining 80,000 troops entered and were intercepted, and then fell into the encirclement.

After stopping the enemy, the infantry artillery and other troops of the Southern Navy followed, and the complete encirclement was completed that night.

The next day, the Southern Navy launched a large-scale attack on the enemy forces in the encirclement!

The mobile operation envisioned by Yuan Yonghan was unsuccessful, and the battle once again evolved into a positional offensive and defensive battle.

In this case, the encircled troops under Yuan Yonghan were unable to resist at all.

At noon, large-scale surrenders began to appear among the Dongdingzhou troops trapped in the encirclement.

Wait until four o'clock in the afternoon, the last 20,000 recalcitrant Dongdingzhou troops, led by their senior generals, announced their surrender!

In just two days, more than 80,000 of the 100,000 troops deployed by Yuan Yonghan on the first line of defense were wiped out and captured.

If it is an exaggeration, Yuan Yonghan spent months painstakingly operating the Hetai defense line, but it could not hold up for an hour.

Although there was a reason why Yuan Yonghan took the initiative to give up, this still could not change the fact that the Hetai defense line was conquered within an hour and 80,000 troops were annihilated within two days.

After the last main force of the enemy army surrendered, Lin Ziran didn't even have time to wait for the detailed battle report to be reported, and directly ordered the troops to continue to advance, and at the same time strictly ordered the logistics department to do a good job in logistics supply, make good use of the Nanluo River, and transport a large number of materials to the front line.

After Yuan Yonghan fled back to the second line of defense with 20,000 remnants of his soldiers, he did not mobilize troops to deploy the so-called second line of defense at all, but retreated directly with the troops of the second line of defense.

Immediately after him, he took away the troops of the third line of defense!

Less than three days after the start of the war zone, Yuan Yonghan directly abandoned the three lines of defense in front, with a strategic depth of more than 50 kilometers, and rushed all the way to the east with the remnants of the army of more than 100,000 people!

Where to go?

To be honest, Yuan Yonghan didn't know.

But the only thing he knows is that he must not stay and resist the Southern Navy head-on, which is undoubtedly hitting a stone with an egg.

The previous rout of the Hetai defense line was already a frontal battle of the Southern Navy's formidable ability to fight head-on, and he definitely didn't want to experience it a second time.

Yuan Yonghan gave up resistance and retreated directly to the north with a large army, which almost voluntarily gave up a large area of his control, which made the Eastern Expedition of the Southern Navy more smooth!