Chemical warfare in World War I evolved from banned weapons to devastating battlefield tactics, beginning with the first deadly gas attack on April 22, 1915, when Germans released 160 tons of chlorine gas at Ypres, killing French colonial soldiers who had no protection; this sparked an arms race where both sides developed increasingly sophisticated gas masks and more deadly agents like phosgene (12 times more lethal than chlorine) and mustard gas (the most feared weapon due to its ability to cause blindness and severe burns while having the lowest death rate), ultimately leading to the 1925 Geneva Protocol banning chemical weapons, though approximately 66 million gas shells were fired during the war and one-third remain unexploded today.
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The Cruelest Chemical Weapon of WWI
Added:The scariest chemical weapon of the First World War was never really meant to kill you. Instead, it did something that hurt an army far more than a dead soldier ever could. However, it was just one of the chemicals used in this war.
And they all did some really disturbing things to the human body. When the war went wrong for all sides on the Western Front already in 1914, with the expectation of that fast decisive war shattered by the trench stalemate, military planners were scratching their heads, thinking, "Now what?" Any attempt to break the deadlock ended with pretty much the same result. Thousands of men dying in failed assault after failed assault without achieving anything significant. It became so bad that all sides realized they were going to run out of men to fight at this pace. So they turned to other tactics that were up until then seen as impractical or cowardly like digging tunnels under no man's land or more importantly using poison. This is how the absolutely worst kind of weapon of the entire first world war was born. The chemical weapons. Now long before the great war began, using poison and similar weapons was seen as a disgrace in an otherwise pretty noble way of fighting the war with rifles, artillery, and bayonets. That's all cool, but poison was considered a sneaky and cowardly way to fight. Such weapons were banned in several conventions before the war. However, that moral high ground went out the window pretty damn quickly as the trench horrors developed.
The French started first with small tear gas grenades carrying a strong yet non-lethal irritant to the eyes and lungs. It turns out it didn't do much.
The Germans then tried the same thing when they fired some 18,000 tear gas shells at the Russians, which didn't work in the cold winter weather. So, this whole gas thing didn't seem to really work, especially when delivered by artillery shells. The shell could carry only a small amount of gas, and the bursting charge would destroy most of it. So, it all seemed like yet another dead end in the trenches. That was until the Germans got the idea to use their huge chemical industry, which created a bunch of toxic byproducts like chlorine and turn them into weapons.
They came up with the chlorine gas that is heavier than air and so would sink into trenches and dugouts. And instead of deploying it through artillery shells, they'd release it from pressurized cylinders when the wind was blowing toward the enemy side. You see, those conventions that banned poisonous weapons had a loophole because they applied to projectiles whose sole object was to spread some form of poison. And if you just release the poisonous gas from thousands of cylinders, you're not breaking any rules. Technically, although these conventions were about to be torn up anyway, as no one had a better idea of how to win the war. By the early spring of 1915, the Germans had quietly buried thousands of these cylinders filled with chlorine gas in forward trenches nearra in Belgium, where the Allied line pushed forward into German held territory. Now, the whole plan depended on the right wind and in this area, the wind usually blew from the Allied side toward the German side. So, the cylinders were waiting for the perfect moment for weeks. During that time, a German deserter crossed the line, surrendered, told the Allies that a gas attack was being prepared and showed them the simple cottonmouth pan that German soldiers were issued for their own protection. But the warning was largely brushed aside and not taken seriously since it came from the man who had just revealed the whole plan to his enemies. So, pretty much no precautions were put in place. However, on the evening of the 22nd of April, 1915, the wind started blowing from the German side toward the Allied side, and around 5:00, the Germans opened a short artillery bombardment, during which the valves on some 5700 cylinders were opened, and 160 tons of chlorine were released along a 4-mile front line. A yellowish green cloud was slowly being carried over no man's land and down into Allied trenches. And the men directly in its path were French colonial soldiers.
They had no protective gear whatsoever.
And they didn't even know what this cloud was. They thought that it must be a smoke cover for an incoming infantry attack. So with no other choice, they waited in their trenches until the cloud reached them. And when they realized what this cloud actually was, it was already too late. Their eyes started burning. and then their noses and throats and the pain reached down into the lungs. Uncontrollable coughing and then a choking sensation followed.
Soldiers ran out of their trenches in panic. But by this point, no one could help them. They inhaled more than a lethal amount of chlorine. And what chlorine does to a human body is it dissolves in water. So whenever you naturally have wet places in your body, like your eyes, nose, throat, and most importantly, the lungs, that's where the chlorine gas is going to turn into acid.
And you can already imagine what the acid does to the eyes or throat, but you definitely can't imagine what it does to the lungs. Because the lungs are damp and you'd be breathing this gas in and collecting it there. They got hit the hardest. And when the gas becomes acid inside the lungs, it burns and destroys the cells it touches. Then, as a result, the lungs get filled with fluid. And the actual cause of death for the unfortunate soldier is drowning.
Literally slow drowning from the inside.
and I don't even want to think about what that would feel like. Death came minutes or hours after the attack, and everything depended on how much of the gas the soldier inhaled. However, surviving the first day was no guarantee either, as many died over the following days from complications from their damaged lungs, like septic pneumonia, and even those who lived through the gas attacks carried breathing troubles with them for the rest of their lives. Now, going back to the first ever deadly gas attack, the morbid thing is that even the Germans didn't expect it to be so horrifically effective. The French line in the path of the chlorine cloud simply came apart with men either dead in the trenches or running back to the rear. A hole of about 4 miles opened in the Allied line for the first time in the war. However, the Germans weren't ready to use this breakthrough as there were no prepared reserves to push forward and hold the ground. The German soldiers who were given those simple gauze pads as improvised gas masks weren't really eager to go forward when they'd seen what this gas did to the French. So that hesitation bought the Allies just enough time and the British and Canadian troops were rushed to fill the gap in the line.
This was the first proper deadly gas attack of the war, but definitely not the last one. The game was now on, and chemical weapons would only get deadlier and disturbingly creative in how they killed. The attack left around 6,000 casualties, but the Germans launched another one just 2 days later in the same way, only now against the Canadians. However, by then, the word had spread that a wet cloth pressed over the nose and mouth could reduce the effects of chlorine. So, Canadian troops did what they could to protect themselves. They even soaked the cloth with urine when they didn't have water and then, you know, pressed it over their mouths. But hey, it's still better than getting gas. Now, this new disturbing weapon started a cat-and- mouse game of who'd make the better gas mask to protect their soldiers and who'd make the deadlier chemical weapon to defeat the enemy's gas masks. The British replaced the simple chemically treated cloth with the black veil respirator, which was fragile and awkward and gave only weak protection.
Then came a flannel back, also known as the British smoke hood, which went over the entire head with a filter containing a solution that neutralized chlorine.
The Germans, meanwhile, got a much better rubberized mask with a screw on filter drum, pretty similar to the gas masks that we have today. The British then made their own first gas attack the same way the Germans did with those cylinders. Although part of the chlorine cloud was blown back to their own lines and actually killed more British than German soldiers. But anyway, the race was now on. And these early masks, crude as they were, still did a relatively good job of keeping a man alive under a chlorine gas attack. So the Germans then came up with something around 12 times deadlier than chlorine. More importantly, it was sneaky. As this method of releasing the gas from cylinders was risky and depended on the right wind, and the gas masks defeated chlorine relatively easily, it was time for fosgene to come into play. Some sources state the French were the first ones to use it, while the majority say it was the Germans. But either way, this new gas was at first mixed with chlorine and released from cylinders just like before. Fostgene is a colorless gas with only a faint smell described as musty hay or freshly cut grass. Unlike chlorine, which reacts immediately and violently the moment it touches the wet parts of the body, this one worked slowly and quietly instead. And it defeated the gas masks that were good against chlorine. Because it was nearly invisible and had a barely recognizable smell. And because it didn't show its effects immediately, a soldier would breathe in several times the lethal dose and walk away thinking he was fine.
However, Fosgene had already reached the alvioli where it slowly began breaking down into hydrochloric acid, which in the same way as chlorine destroyed the lungs from deep inside. Over the next several hours, the fluid began leaking into the lungs. The flooding built and peaked about 12 hours after exposure when the unfortunate soldier began to drown from the inside. The same effect as chlorine only much more powerful and delayed which made it so much deadlier.
Forgene would also be used by the allies and it caused 80% of all gas deaths in the entire war. The British had to evolve their gas masks again. And in 1916, they finally came up with the small box respirator, which had a separate canister of charcoal and neutralizing chemicals, and reliably protected the soldiers from gas if put on in time. However, if you think the worst part is over, well, think again.
Because the real deal with the gas was only about to begin as the delivery method changed and the chemicals became deadlier. The first thing was that they finally found a way to pack gas into artillery shells. So they now didn't need to wait for the wind. They also began mixing them with the standard high explosive barrage to mask the gas shells because they had a distinctive like low blooping sound and soldiers would immediately put on their gas masks. So now they never knew when the gas attack might come. Is it safe or not? Has it passed or does it still linger in the dugouts and the shell craters? Is the gas mask working? Now think for a moment about seeing someone die in such a way and then wondering whether the same is going to happen to you at any moment.
Now think about that for months on end and you might begin to understand the term shell shock. However, the game continued on. The Germans developed so-called sneeze agents and put them in artillery shells which they called mask breakers. The idea was to find them mixed with the force gene shells. And these powerful irritant particles could go through a mask's filter and then set off violent, uncontrollable sneezing and coughing or even vomiting, which would force a soldier to take off this gas mask. And then you know how it goes from there. By 1917, this constant back and forth had completely changed the situation in the trenches. And while this was happening on all fronts, the most concentrated and worst of it by far was on the Western Front. Then when the American army entered the war in 1917, it was horribly underprepared for this new gas war. They had no gas masks, no gas training, and no chemical weapons.
So they had to lean on the British and French to catch up. And they arrived just as the chemical warfare reached its most devastating form yet. This is why despite their short time in the war, they got the highest rate of gas casualties of all countries. Now, just as the masks evolved to protect these soldiers reliably enough from chlorine and fosgene variants, the weapons evolved again. On the night of the 12th of July 1917 near Epra, on the eve of the great British offensive, the Germans fired around 50,000 shells carrying roughly 125 tons of a new agent. This was sulfur mustard, more widely known as mustard gas. In fact, it was a heavy oily liquid, yellowish or brownish in color that smelled like garlic. And like Fostgene, it gave almost no immediate warning besides a faint smell and mild irritation. Upon bursting, the mustard shells scattered fine droplets that clung to everything they touched and then slowly vaporized for up to several days. And what made mustard the most feared was not how lethal it was.
Because of all the killing gases, mustard had the lowest death rate. That day, out of roughly 2500 British gas casualties, only 87 died. It was feared because it was built to maim, disfigure, and overwhelm rather than to kill. And that, coupled with being incredibly difficult to detect, made it far more effective than other chemicals. It's what chemists call a blistering agent, which means it destroys the cells it touches, but only hours after being exposed. Soldiers would get sprayed by mustard or go into a contaminated area days or even weeks after the attack in colder weather. And then they'd get back into their dugouts where it was warm. So the mustard started vaporizing. By the morning, everyone in that dugout was done as they breathe the agent into their lungs. The eyes were hit first and worst and they swelled shut causing temporary or permanent blindness. Those photos you might have seen where dozens of soldiers are holding on to one another in columns. Well, those were the blinded mustard victims. Other parts of the body that naturally have more moisture were attacked the most, especially, you know, down there with horrible burns and blisters all over the skin, which were incredibly difficult to heal and could easily get infected.
Stretcherbearers, nurses, and doctors who handled contaminated soldiers were all victims of mustard. And here's why it was so disturbingly effective in war.
It caused so many casualties in such a short time that it completely overwhelmed the field hospitals and evacuation system. And a wounded man actually causes more damage to the enemy than a dead one. Someone needed to take care of them and to bring all that chaos under control, which only drained further resources and wasted time that the other side could exploit to win the battle. Not to mention the blow to morale after such attacks. because describing the sight of hundreds of men in agony wouldn't keep this video on YouTube. But you get the idea. Chemical warfare now evolved into a horrific routine with a whole catalog of shells and agents that all sides were mixing to get the deadliest possible result.
Shells were marked with different colors. For example, a green cross for Fostgene, a blue cross for the so-called mask breakers, a yellow cross for mustard, and so on. Soldiers devised warning signals for gas attacks. So when anyone suspected gas, they'd raise the alarm that would be passed down the line, usually tapping on improvised gongs, bells, rattles, or even horns to signal everyone with an earshot to put his mask on. And not only men in the trenches were getting killed by the gas.
Keep in mind that there were millions of horses, mules, dogs, carrier pigeons, and other animals that suffered just the same. Soldiers tried to protect them with improvised gas masks, but the animals was sadly just collateral damage. The same went for civilians in towns and villages around the front lines when the gas drifted towards them.
The horrors of chemical warfare and World War I pushed the powers to sign the 1925 Geneva Protocol, which banned the use of chemical and biological weapons in war, although without saying anything about developing and stockpiling them. So, it was more of a promise like an I won't use it if you don't use it first sort of thing. Around 66 million gas shells were fired over the course of the war, plus mountains of leftovers when it finally ended. Most of which were really carefully and safely disposed of by dropping them into the sea and waiting for the salt water to corrode them and let the gas agents leak out. Freaking genius. However, the end of the war didn't mean the end of gas killing people because about a third of those shells failed to detonate. So, you do the math yourself on how many are still lying somewhere filled with chemicals that would ruin your life.
They're still being recovered to this day by unfortunate farmers or construction workers digging in the ground in France and Belgium.
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