Time Machine (1915): When chemicals became weapons in WWI

Transcription

1 Time Machine (1915): When chemicals became weapons in WWI By Scientific American, adapted by Newsela staff on Word Count 937 Level 1030L Three models of respirators to prevent ingesting poisonous gas. Scientific American Newsela Editor's Note: This article originally appeared in the June 12, 1915, edition of Scientific American, under the title "The Use of Poisonous Gasses in Warfare." The earliest recorded use of poisonous gases in siege warfare was in the Peloponnesian wars from 431 to 404 B.C. Persian forces besieged two Greek cities. Wood saturated with pitch, a sticky black substance, and sulfur was set on fire to generate choking and poisonous fumes that would sicken defenders. In the years 1261 and 1412, the Byzantine Greeks used a liquid of unknown composition at the sieges of Constantinople. Called Greek-fire, it was squirted through the air and set fire to the places attacked. We turn now to the current war. What follows are official descriptions of the character, appearance and effects of poisonous gases used by Germans in trench warfare. This article is available at 5 reading levels at 1

2 Gases Cause Death, Permanent Injury One describes gases being ejected from pipes laid in the trenches and also produced by the explosion of specially manufactured shells. The German troops wore specially designed respirators and attacked under cover of these gases. This poison is described as not merely disabling or painlessly fatal, as the German press suggests. Victims who do not die on the field suffer greatly. Most die a painful, lingering death. Those who survive appear to have permanent injury to the lungs and will likely be invalids for life. These effects must be well known to the German scientists who devised this new weapon and to the military authorities who have sanctioned its use. Another, by a British officer, describes the effects of the poison gases on the men who survived them. It tells of men desperate to take in breath. Their faces, arms and hands were of a shiny gray-black color, with mouths open and lead-glazed eyes. All swayed slightly backward and forward, struggling for breath, struggling for life. A French research scientist was sent out to investigate the effects of these gases. The symptoms he witnessed point to the use of chlorine or bromine by the German troops. The purpose of these gases was to suffocate people, or cause them to be unable to breathe. Sulfur, Chlorine Drift Into Trenches Our last description comes from a captain in the Canadian army who was in a trench about 600 yards from German lines. He saw a white smoke rising about three feet from the German trenches. In front of the white smoke appeared a greenish cloud. It drifted along the ground to their trenches, no more than seven feet from the ground. Men in these trenches were forced to leave. A number of them were killed by the effects of the gases. The last description indicates that the gases used in this attack were a mixture of sulfurous acid and chlorine. The former is a dense white gas. The latter is green. Both gases are heavier than air and creep along the ground. They can be generated simply, cheaply and in large quantities. When inhaled without much air diluting the gases, both gases are suffocating. The sulfurous acid gas was probably made in the trenches. The chlorine was probably carried in large steel cylinders in liquid form. German military authorities have quite possibly accumulated large stocks of chlorine. They have plenty more ready in salt deposits in Germany. With cylinders of compressed chlorine in the trenches, all that is needed to do is to insert a delivery pipe through the outer wall of the trench and connect it to the cylinder. Then wait for a favoring wind before turning on the gas. The gas will escape under its own pressure. First Respirators Not An Effective Defense Let us turn now to the practical question of how to defend against poisonous gases. These may be divided into two broad classes: respirators and counter air flow. This article is available at 5 reading levels at 2

3 Over a million respirators were supplied to British troops toward the end of April. These first respirators consist of a loose cotton and wool fabric covering the mouth and nose. They have not proved effective against the gases when they are condensed. The French are experimenting with larger helmet-shaped respirators and head coverings. When working with chlorine and sulfurous acid gases, if the air is not too heavy with these gases, relief in breathing can be obtained by a mouth cover made of thick fabric. This "gag" is held tightly over the mouth while you breathe in through the mouth and exhale by the nose. With the aid of this simple respirator, it is possible to stay in an atmosphere lightly charged with chlorine or sulfurous acid for some minutes. More heavily charged atmospheres require a thicker roll of fabric. Pumps Might Push Gas Cloud Away The other practical method of meeting these gas attacks is to create a counter air current. This would roll the cloud of poisonous gases back as it drifted over the Allies' trenches. It might be possible for army engineers to adapt plane engines and propellers for this work. Or they could arrange for gasoline-operated air pumps to be stationed at points most likely to be subject to gas attacks. These attacks are delivered only with a light breeze. In a strong wind, the gases are carried over the Allies' trenches too quickly to cause much harm. A slight counter air current ought to be enough to change the direction of the gas cloud. These anti-gas fans and pumps would have to be well hidden and protected. Otherwise they would be smashed by enemy fire. Placed in the rear of the first line of trenches, they should prove of great service in turning back attacks of poisonous vapor. This article is available at 5 reading levels at 3

4 Quiz 1 Which statement would be MOST important to include in a summary of the article? The earliest recorded use of poisonous gases in siege warfare was in the Peloponnesian wars from 431 to 404 B.C. This poison is described as not merely disabling or painlessly fatal, as the German press suggests. Let us turn now to the practical question of how to defend against poisonous gases. These may be divided into two broad classes: respirators and counter air flow. When working with chlorine and sulfurous acid gases, if the air is not too heavy with these gases, relief in breathing can be obtained by a mouth cover made of thick fabric. 2 Which sentence in the section "Gases Cause Death, Permanent Injury" BEST summarizes the effects of the poisonous gases used by Germans? The German troops wore specially designed respirators and attacked under cover of these gases. All swayed slightly backward and forward, struggling for breath, struggling for life. A French research scientist was sent out to investigate the effects of these gases. The symptoms he witnessed point to the use of chlorine or bromine by the German troops. 3 Why does the author describe the appearance of the poisonous gases? to compare these gases to other types of poisonous gases to contrast Germany's use of gases with the Allies' tactics to explain how people identified the types of gases that were used to suggest a solution that would neutralize the poisonous gases 4 Read the introduction of the article [paragraphs 1-2, after the Newsela Editor's Note]. What purpose does the introduction serve in developing the central idea? It shows similarities between gases used in earlier time periods. It shows differences between gases used in earlier time periods. It shows where Germans got the idea to use poisonous gases. It gives background information on gases used in earlier time periods. This article is available at 5 reading levels at 4

5 This article is available at 5 reading levels at 5