After Dong Hu stayed in Xinjin City for two days, he got up and rushed back. Compared to when they came, their return journey was much faster. This was due to the fact that the return trip was lightly equipped - expensive gifts were given to Pan Tong, and even the grenades were only a few new grenades left. All the old grenades have been given to the craftsmen of Xinjin Castle. The grenade detonated by the new type of mine mercury is still in the secret stage, and it must not be sent, of course, even if it is sent to Xinjin City, it cannot be imitated. Without the industrial system of the Thunderbolt Army, even if Xinjin City imitates an old-fashioned grenade, it will definitely not be as powerful as the Thunderbolt Army. The reason for this is that it is one thing to know the principles and methods of grenade manufacturing, but the key is to have high-quality raw materials and mature technological processes, and it is inseparable from a sound quality and management system. Another reason for the fast return speed was that the Mongolian cavalry activities were missing along the way, which allowed Dong Hu and the others to no longer have to cross the quagmire path, but boldly advance along the official road, and the footsteps were of course much faster, which made Dong Hu and the others arrive near Chongqing Mansion at dusk on the day of departure.

Looking at the city of Chongqing in the distance, Dong Hu decided to take the risk of approaching to reconnoiter in order to grasp the military intelligence such as the strength and defense of the troops in the city. In his letter to Ouyang Xuan, Pan Tongzhi had asked the Thunderbolt army to prepare and wait for the order of Pu Xuezhi, the Sichuan envoy and prefect of Chongqing, after the Spring Festival.

Taking advantage of the cover of night and water mist, Dong Hu and the five of them quietly sneaked to the island in the middle of the Wenjing River outside Fucheng. This island in the center of the river is formed by the alluvial sediment of the river, about 500 meters long and about 100 meters wide, and is about 100 meters away from the wharf outside the west gate of Fucheng. There is a large forest in the middle of the island in the middle of the river, and there is a camp of the Chongqing Navy army in the forest. When Pan's command evacuated, he took all the ships with him, and the barracks were abandoned, leaving only a few dozen dilapidated thatched huts. Dong Hu saw that the trees were tall and dense and facing the city, so he prepared to hide here for the night, and climbed up to the treetops to observe the situation in the city after dawn. As they approached the abandoned barracks, they heard the sound of low conversation coming from a grass hut, and the broken walls were glowing with fire. Dong Hu and the others crept over, and from the broken wall, they saw that there were only two thin teenagers in ragged clothes, one big and one small, in the grass hut, and there was no one else. The two half-sized men were sitting around the campfire in front of them, warming themselves in broken clay pots. Facing Dong Hu and the others who suddenly walked into the grass hut, the two teenagers did not panic or run away, but the older boys calmly invited them to roast the fire. Under the firelight, although the two teenagers were unkempt but bright-eyed, their calm and easy expressions made Dong Hu and the others sigh in their hearts, and they also sat around the fire and asked them about it.

Dong Hu and others learned that the two teenagers were brothers. The elder brother's name is Xia Dagen, and his brother's name is Xia Xiaogen, who is ten years old this year. When the Mongols came, his father was unwilling to retreat to Xinjin City with Pan's rule and stayed in Chongqing City, and was later killed by the new annexed army because he was unwilling to surrender to the Mongols, and his mother also died in the raids of the rebels. The two brothers could not gain a foothold in the city, so they came to this abandoned military camp to find a way to survive, and lived by digging wild vegetables on weekdays, but fortunately there were many wild vegetables here, and they could also catch some fish, crabs, mice, frogs and other small animals, and their father's old friends would occasionally send some food, but they also survived. Now the broken clay pot on the fire is stewed with plant roots and wild vegetables. Dong Hu and the others gave some salted meat, shortbread and other dry food to the two brothers, and ate a round belly together on wild vegetable soup.

After eating and drinking, the two brothers' faces were also a little rosy, and Dong Hu asked curiously why they weren't afraid when they saw strangers, why didn't they run away? A trace of sadness flashed in Xia Dagen's eyes, and he said lightly: "If Uncle Dong and the others are wicked people, if they want to cause harm, my two brothers can't beat them, they can't escape, they can't escape, it's useless to beg, it's better to face it calmly and have a trace of decent ......." Xia Dagen's mature mind and the calmness of the young man made Dong Hu and others sigh, he was sure that these two brothers would be the pillars of the army when they grew up, and immediately invited them to attach themselves to the Thunderbolt Army. Hearing that he would have to reconnoiter the situation in the city tomorrow, Xia Dagen told Dong Hu that his father had a close friend named Liao Loach before his death, and he was now the leader of the new attached army. Without waiting for Xia Dagen to finish speaking, Xia Xiaogen volunteered that he could sneak into the city at a young age, and notified Uncle Yu to come on the grounds that his brother was sick, just hoping not to hurt Liao Loach. Dong Hu agreed to this reasonable request, and secretly marveled at the courage and resourcefulness of these two brothers. They immediately discussed going their separate ways after dawn.

At the beginning of the dawn, Xia Xiaogen had quietly hidden the simple raft across the river in the reeds on the dock outside the city, and he wanted to mix in with the flow of people who sent vegetables, firewood and grass into the city when the city gate was just opened. Dong Hu asked his subordinates to climb up to the treetops to observe the situation in the city, and he took Xia Dagen to observe the situation on the other side of the river in the reeds.

For about half an hour, the scouts on the tree quietly descended from the tree and sneaked to Dong Hu's side. They saw a depression in the city, the houses near the east gate were demolished into open space and turned into a racecourse, as for the situation of the city's defenses, they could only see a rough idea, and they could only judge that the city wall covered with blue bricks was tall and wide, and the horse-faced and saucer buildings were also all available. Just when Dong Hu and the others lamented that this fortified city with strong defense was easily abandoned by Pan's system, Xia Xiaogen appeared on the other side of the river with people.

As soon as Liao Loach dragged the raft to the shore, he saw several sturdy men coming out of the reeds, and he was frightened and wanted to turn around and jump into the water, but was stopped by the two brothers. In fact, although Dong Hu and the others had surrounded him at this time, if he jumped into the water, no one would be able to stop him. In other words, this Liao loach is really as good as its name, and the winter is also short, and the rest of the body except for the teeth are dark. Of course, his loach got its name more from its excellent water nature, and his reputation was as far as Xinjin and Pengshan Shuijun, and everyone called him Liao Loach, and over time even he forgot his real name. After Xia Dagen and Xiaogen explained the situation in detail, Dong Hu and the others also said a few words of relief, and his frightened gray face slowly turned red and black, and he quickly told the information he knew.

According to Liao Loach, after Pan's retreat to Xinjin City, the 1,000 soldiers who remained in the city became chaotic, more than 300 people left the city to become bandits, and the rest surrendered to the Mongols and became the new annexed army. In order to control this new annexary army, the Mongols sent a Semu man to be the leader. In addition to the new annex army of more than 600 people, there were originally 500 Mongolian and Han cavalry stationed in the city, but most of the cavalry were transferred to Chengdu Mansion in the first two days, and now there is only one hundred-man team. Because of the lack of food and grass and because most of the cavalry was transferred, the Mongol army no longer went out on patrol on a large scale but stuck to the city. The captain of the Mongolian army of 100 and the leader of the new annexed army no longer went out to plunder, but drank and had fun all day long.