Tao Zhiguo said this, took out a white handkerchief and wiped the sweat from his forehead, and continued to tell the story that seemed to belong to him.

"Gas blowing cylinders, the simplest and most effective chemical weapons, showed great power in the early days of war. But as the war progressed, its limitations became more and more apparent. So, people turned their attention to chemical shells again. ”

"The Germans, on the basis of the earlier stimulus chemical shells they developed, began to move towards the development of lethal chemical shells, that is, double phosgene shells. Also known as the 'Green Cross' bomb. This is because the marking system used by German chemical weapons is the colored 'ten', which represents the surname of the internal agent: 'green cross' means the volatile agent that causes respiratory tract damage, 'yellow cross' means non-volatile agent, especially the agent that damages the skin, 'white cross' means tear gas, 'blue cross' means sneezing agent, and 'red cross' means the so-called 'irritation agent'. Originally used in 1916, the Green Cross was available in three variants, fired from 77mm, 105mm and 150mm field and howitzer guns, with the same body design as earlier chemical shells. At the end of 1916, the Germans improved this type of ammunition by using a special shell containing chemical agents, which was longer than the original case, and had a thinner wall, and at the same time was dispersed only by the explosive of the detonating tube, which increased the loading capacity of the poison. By August 1917, the 'Green Cross' was used in all German field artillery. ”

"Not far behind, French designers invented the so-called 'No. 5 special projectile' with phosgene, that is, shells for 75-mm field guns. This field gun compensated for the lack of ammunition weight with its very high rate of fire and was supplemented by shells from 105-mm and 155-mm field and howitzer guns. In the Battle of Verdun, it was successfully used for the first time, proving to the world that this is a very effective chemical warfare technology that does not require heavy poison gas cylinders, which has attracted the general attention of the belligerents, so they have imitated and developed it. By 1917, artillery had become the primary means of delivering chemical warfare agents, and all belligerents fired chemical bombs on a massive scale. ”

"The Battle of Verdun, fought on the Western Front in Europe from February to December 1916, was the largest and longest battle of the First World War. The battle, which lasted 10 months and resulted in nearly 1.6 million casualties on both sides, earned it the nickname 'meat grinder' or 'human flesh mill'. It has become a testing ground for new weapons and new tactics, and all kinds of old and new poisons are also competing here. ”

"Verdun is one of the famous fortresses in France, which began to be built in 1914, and after nearly two years, a very strong and complete fortified area was built, and four defensive positions were built, 2 to 3 kilometers between each position, and the total depth was 45 kilometers. The entire defensive front is 112 km. It was not easy for the Germans to break through this line of defense. So at the very beginning of the Battle of Verdun, the German and French armies used a lot of chemical shells in artillery fire preparation or counterattacks. The Germans began at 8:12 on February 21 and prepared for nine hours with 1,500 guns. One hour before the attack, artillery fire reached its heaviest intensity, and a large number of chemical shells were fired, enveloping the French troops in poison gas. ”

At this time, Tao Zhiguo seemed to have returned to the battlefield of Europe and was in the "Verdun Hell".

In front of Tao Zhiguo's eyes, that terrifying scene appeared again.

The ground trembled under the feet as thousands of cannons were fired at the same time, and a dull roar followed by a flickering of dark red fire. Modified gas cylinders and chemical shells flew through the air, flipped awkwardly, and then poured heavily on the position. In an instant, the poison bomb containing phosgene exploded, and nearly 50 tons of phosgene quickly evaporated and vaporized, forming a dense cloud of poisonous gas.

The terror caused by the mixture of poison gas smoke and artillery bombardment had already terrified the soldiers on the position. Where the gas hit, the French soldiers retreated, and only a group of Chinese artillerymen with gas masks continued to resist, constantly firing at each other, but soon the ammunition ran out. Soon, they were completely overwhelmed by deadly artillery fire and smoke clouds of poison gas......

Terrible clouds of gas smoke and artillery fire created a death zone that no unit could hold. Fragments of steel, grenade fragments, and poison gas rained down on the woods, ravines, trenches, and shelters where the soldiers were, as if to wipe everything out......

"Phosgene is an important raw material for the synthetic dye industry, and its scientific name is carbonyl dichloride. In 1812 the English chemist John ? David synthesized phosgene from carbon monoxide and chlorine in the light of day. Because it is a photochemical synthesis, it is a phosgene, from which it is obtained. ”

"Phosgene is a colorless gas, with the smell of rotten hay and rotten fruit, it evaporates quickly, it is very easy to reach the concentration of harm, its poison is 8 times that of chlorine, and it is enough for people to be fatally exposed to 4 to 5 grams of phosgene per meter in the air for 1 minute, phosgene mainly passes through the respiratory tract in the form of gas and causes poisoning. After inhaling phosgene, you will obviously feel chest tightness, dry throat, cough, dizziness, nausea, and after 2 to 8 hours, you will have severe cough, dyspnea, headache, bruised skin, and cough up light red foamy sputum, and when the poisoning is severe, you will suffocate to death. ”

"Phosgene is a typical representative of the poison surnamed asphyxiation, and it is also the most lethal poison in the First World War, and 80 percent of the people who died from poisoning during the war were due to phosgene poisoning. Because phosgene poisoning has an incubation period for a period of time, it is easy to paralyze people's minds, so it is often that many people do not know that they are poisoned at first, and they can still perform tasks that day, still eat and sleep, but suddenly die the next day......"

Speaking of this, Tao Zhiguo seemed to be unable to control his emotions anymore, he slammed down on the podium, covered his face with his hands, and cried out like a child.

The students in the audience and the organizers of the class were all a little shocked when they saw this scene, and the female officer, as if she knew what was happening, hurried to the podium, held him to his crumbling body, comforted him softly, and led him off the podium.

At this moment, the bell rang for the end of class, and the students got up and left the classroom. When the students passed through the hallway, they found Tao Zhiguo and the female officer sitting on a bench in the hallway, Tao Zhiguo buried his face in his hands, still crying. From time to time, the male and female students cast curious glances at the two of them, but the female officer only looked at him tenderly, oblivious to the students' gaze.

After a long time, Tao Zhiguo stopped crying, he raised his head, took out a handkerchief to wipe the tears from his face, and looked at the female officer sitting next to him with some embarrassment.

"Makes you laugh, Nan Nan." Tao Zhiguo said to the female officer, his wife, Army Captain Cheng Nan.

"What's the matter?" Cheng Nan smiled slightly and held his hand, "I also came back from Europe, and there are too many unforgettable places in that war." When many sisters go to the military cemetery to pay respects, they will cry to death. ”

"Yes! So when I teach such a class, I can't control my emotions at all. Tao Zhiguo sniffled and said in a hoarse voice.

Cheng Nan gently stroked his hand, and when her soft fingertips gently stroked a scar on his wrist, she couldn't help but tremble slightly.

"Is this gas?" Cheng Nan asked, "Is it phosgene?" ”

"No, it's mustard gas." Tao Zhiguo replied.

"Mustard gas?" Cheng Nan asked a little strangely, "Is it the kind of poison gas that is called the 'King of Poison Gas'?" ”

"Yes, you know, with the continuous emergence of new poisons and their extensive use on the battlefield, all kinds of gas masks have gradually been produced and improved, gas masks have been enough to protect against poisons poisoned through the respiratory tract, which makes the battlefield use of chemical weapons greatly reduced, at this time the Germans quietly developed a new poison, the mode of action from the respiratory tract to the skin, this is mustard gas." Tao Zhiguo nodded and said.

"The scientific name of mustard gas is dichlorodiethyl sulfide, and the pure product is a colorless oily liquid, with garlic or mustard flavor, which is not easy to decompose and volatilize at general temperature, insoluble in water, and soluble in organic solvents such as gasoline and alcohol. It has a strong ability to penetrate, and skin contact with mustard gas droplets or aerosols can cause redness, swelling, blistering, and even ulceration. ”

"That's amazing." Cheng Nan's eyes widened in surprise.

"The German use of mustard gas shells for only three weeks had a higher lethality rate than all poison shells in previous years. The British and French troops suffered heavy casualties, still at Ypres, and I remember it was a mild summer night on June 14, 1918. At about 10 o'clock, suddenly the quiet night sky was broken by the rumbling of artillery from the German positions, and a large number of 77-mm and 105-mm shells screamed and flew towards the positions of our troops. As soon as the British heard the sound of the cannons, they hurriedly hid in bunkers, and complained there that they were sorry for the destruction of such a beautiful night, and kept nagging: these damned Germans don't know how to be romantic! ”

Hearing Tao Zhiguo's humor, Cheng Nan couldn't help but purse his lips and laugh. But her husband's recounting soon ended her light-hearted laughter.

"But at that time, whether it was the British, the French, or us, we did not know that the poison demon had quietly stretched out its evil hand to us, because this time the Germans fired not ordinary artillery shells, nor the poison gas bombs that the soldiers were familiar with, but mustard gas poison bombs. When it exploded, the smoke had only a slight irritating effect on the eyes and throat, and there was no other special reaction at first. Some of the soldiers at the time were reluctant to even put on the uncomfortable gas masks, and after wiping off the slimy oily liquid, most quickly went back to sleep. We didn't care at the time. We didn't know that the venom had already infiltrated their bodies, and a few days later there would be an even more disgusting and painful reaction. ”

"In the early hours of the next morning, many soldiers woke up with unbearable pain in their eyes, rubbed their eyes vigorously as if there was grit grinding in them, and then vomited incessantly. By the time it got dark, the eyes hurt even more, and they had to take morphine for temporary relief. On the third day, when the sun rose, the whole army was as if it had a plague, and the deplorable condition was indescribable, and the people shuddered to watch. Many were unable to move, and some of the less poisoned wounded were like blind people, unable to walk, and had to be led into ambulances by paramedics when they were evacuated. Their faces were bloodshot and swollen, especially those who were seriously injured who were carried up, and many had small blisters on the lower part of their faces and necks. A small number of wounded people also had painful small blisters on their thighs, backs and buttocks, and even in the scrotum. This is caused by the fact that they sat on the ground contaminated with mustard gas, and the poison seeped into the skin. A chemical warfare adviser in the British army tried to collect fragments of mustard gas shells for analysis, and he tried to take away the shrapnel that had been shot into his arm, but the poison droplets on the shrapnel penetrated several layers of his clothing, causing blisters on his chest, wrists, and arms. ”

"The field hospital was full of wounded. Two days after being hit by mustard gas, the first deaths appeared in our army. The process of death after mustard poisoning is a slow and painful process, and there is no specific medicine to treat it, so it can only be watched and let develop. Among these seriously wounded, some died directly from poison burns, and some died from erosions caused by poison gases in the throats and lungs. All the wounded were coughing incessantly, painful and weak, and many were poisoned, the mucous membranes of the bronchial tubes were peeled off, and some even completely peeled off and became a cylinder; Some victims die with their tracheas completely stuck from head to tail; In some cases, when the corpse was autopsied, the people present could still feel that the smell emanating from it had obvious irritation to the eyes, mouth, throat, nose and face. ”

"I remember standing around an autopsy victim, he had been poisoned a few days ago, but everyone found that the poison was still working after his death, his throat and vocal cords were red and swollen, his trachea was filled with thin foamy fluid, nearly 2 kilograms of pus and blood had seeped into the left lung secretions, the lungs at this time were more than twice the normal amount, hard to the touch, the heart was also filled with blood, twice as heavy as normal, and the blood vessels on the surface of the brain gave birth to countless small bubbles. It's particularly scary. ”

"There was a lieutenant, 39 years old, named Zhang Zhongliang, who was a medical officer like me, who died 10 days after being poisoned, and there was a large area of yellowish pigmentation on his body, but there was no watch on his wrist; Significant epidermal burns on the face and scrotal area; The entire trachea and lower part of the throat, including the vocal cords, are encased in a yellowish mucosa; The bronchial tubes are filled with pus; The right lung has atrophied extensively, and there are numerous tracheal pneumonia spots in the profile, which are gray in color, and there is pus in the spots, and many of the pus has flowed out of the bronchial tubes to form fixed pustules; The lungs are congested with fat; Brain tissue is heavily congested due to edema. ”

"The first German attack with mustard gas at Ypre was so successful that it forced our troops to postpone their plans for the offensive for up to two weeks. For the next nine days, the Germans carried out mustard gas attacks on our troops almost every night, continuing to sabotage our army's offensive preparations and dampening our army's offensive spirit. During this period, the Germans poured more than 1 million rounds of mustard gas shells on our positions, causing a total of 25,000 poisoning casualties among our troops and other Allied troops, which is almost the same number as all the casualties caused by the poison gas attacks a year earlier. By the end of the first week, the number of poisoned people in the health team was 2,934; By the end of the second week, it had increased by 6,476; By the end of the third week, another 4,886 people had been added. ”

"Although the mortality rate caused by mustard gas is only 1.5 percent, a poisoned soldier is away from combat duty for at least two to three months, if not longer, and the victim's respiratory system and skin are often re-infected. By the end of the war, thousands of people were receiving disability benefits due to mustard gas poisoning. And because mustard gas is long-lasting, it is still dangerous in areas that have been contaminated with mustard gas in Ypre. Mustard gas venom pits formed in the corners of trenches like shell craters can poison those who touch them and can also contaminate water sources. In winter, it freezes like water and lurks in the dirt, and the following spring, when the earth thaws, it becomes active again and poisons people. Therefore, not only can the polluted trenches no longer be used, but even the passage of such polluted areas must be strictly measured......"

"It's horrible." Cheng Nan sighed and nodded, she now understood why her husband had a nightmarish impression of this poison.

"After the Second Battle of Verdun, the German army suffered a great loss of vitality, because of the addition of us and the American army, the balance of forces between the two sides of the war has changed fundamentally. In order to salvage the defeat, the Germans launched five more large-scale offensive operations in succession, but to no avail. Then our army also had this weapon, and the artillery began to use the same type of poison gas bombs provided by the Americans to carry out fierce attacks on German positions, command posts, communication hubs and rear targets. ”

"At the time of the transition to the general offensive. Both we and the Germans continue to use chemical weapons in large quantities. According to October 1918 statistics, 32 percent of the total casualties of the Allied forces, including our army, were caused by chemical weapons, mainly mustard gas poisoning. ”

"1918 was the year in which the largest number of chemical weapons were used in the Great War, reaching its peak in terms of scale, variety and method. And mustard gas shells were massively used. It's almost to the point that every battle must be used and every day must be used to an astonishing extent. ”

"In the battle to retake Belgium, because chemical weapons were used too much, poison gas clouds filled the land. My clothes, gloves, and boots were covered with speckled droplets, and then my body suddenly felt uncomfortable, my throat was always itchy, and my eyes were as hot as pepper, and although I didn't fall, my whole body was tingling, my eyes were blurred, and I stumbled down from the position. My eyes burned like red coals in a fireplace. Later, he became blind and it was pitch black. The ambulance took me to the hospital, and when the nurse lady saw the huge blisters on my body, she cried in fright. You see the scar on my arm, it's a memorial to that battle......"

(To be continued)