Chemical Warfare - “Gas” In This War - 1918

The Gas Mask Adopted by the United States.

The Gas Mask Adopted by the United States. Close-up view of an American trooper accoutered with a new style gas mask. He penetrated a gas cloud, generated for the occasion, and came out unharmed, although it usually takes an experienced hand to put on a mask securely. History's Greatest War, Pictorial Narrative, Part 7: The Marines, 1919. GGA Image ID # 17ff81ce7f

By Chas. Baskerville, Ph. D., F. C. S.  (Professor of Chemistry and Director of the Laboratories, College of the City of New York; Member War Committee, Technical Societies of America; Expert on Fumes, Noxious Vapors, and Anesthetics)

The Vast Development of a New Military Weapon

A man who carries a gun is pretty sure to have a row some time. A man who carries a gun in his association with peaceful people acquires a definable bravado, which in certain circles is characteristic of a bully.

But there are bullies in other circles, where superior workmanship may be evident, or philosophic discussions take place, even where quotations from the Bible or Shakespeare are cited in verbal support of an argument, and there are bullies who mingle in all these circles.

All of them are characterized by assertive arrogance. If the correctness of the bully’s assertion be questioned by a peaceful person the gun may be shown, or even used.

Righteous indignation prompts one of the gathering to seek a gun for protection, and he may even injure the bully in his clumsy and unaccustomed use of it.

The bully is not necessarily a physical coward, but when he becomes hard pressed and sees red he seeks every device for annihilating those who had questioned his position or opinion. He could not be wrong, in his own opinion, in anything. He stops at nothing to carry his point.

He breaks all the rules governing decent people, just as he gave evidence of his purpose, if need be to him, to disregard the customs of peaceful people beforehand in carrying a gun.

That is the recent history of the German nation, and particularly in this great war. The use of poison gases is just one, but perhaps the most atrocious of his barbaric innovations.

The American chemists, many of whom were former students in Germany, had become restive under the German overbearance. In 1912, when the International Congress of Applied Chemistry convened in the United States, we had disgusting evidence of German arrogance.

Not only did some of the German delegates, like pigs, consume food and drink provided by their hosts, but on their return to the fatherland they put into print criticisms of the management of the Congress and its entertainments.

They even indulged in allusions to the President of the United States, who put himself to great personal inconvenience to meet the delegates of the foreign nations in Washington to extend greetings for our country. Only words of thanks and appreciation of the hospitality extended came from delegates from the civil nations of the world, and practically all were represented.

At least twenty years ago the American universities and schools of technology foresaw the need of breaking away from the influences of German institutions for higher learning and, in spite of the German commercial intrigues, built so that the number of students, especially in the sciences, were provided at home with what was needed.

The relative number of students who went to Germany was materially diminished. By virtue of advertising propaganda of the Germans our chemists failed to receive their dues at home.

Germany was a preeminent specialist in making dyes, and the colors made the noise; but in that field the United States has now found itself. And when this war is over and the accomplishments are summarized it will be found that in the chemistry of war-making, Germany had again been the braggart.

Soldiers at a National Army Cantonment, With Gas Masks Donned, Charging Through a Hail of Exploding Gas Bombs Towards the Imaginary Trenches of the Enemy.

Soldiers at a National Army Cantonment, With Gas Masks Donned, Charging Through a Hail of Exploding Gas Bombs Towards the Imaginary Trenches of the Enemy. Committee on Public Information. The American Review of Reviews, September 1918. GGA Image ID # 17fe49cf46

Poison Gases in Warfare

Poisonous gases are produced by some explosives which have been commonly used in warfare. They are the products of the explosion.

The direct use of poison gases, however, was specifically inhibited by The Hague Convention. They were used deliberately for the first time on April 22, 1915, on part of the Ypres salient.

A poison gas cloud (chlorine) was there launched by the Germans against the French and British, where they joined, the Turcos and Canadians receiving the brunt.

Frustrated in the quick accomplishment of their aims, the Germans again threw all honor aside, as they had done in Belgium, and used poison gases. In this way they proposed to end the war quickly. The immediately bitter purpose was to kill and affect the morale of the colonials.

Written and spoken narratives of the effect of that great greenish-yellow cloud on the minds of those soldiers, as it rose right out of the ground, rolled toward and enveloped them, the first whiffs choking, then producing spasms of agony, are thrillingly terrible.

Many died a horrible death; many who raced away ahead of the weird waves got sufficient of the gas to affect their health seriously.

The morale was not broken, however, and the war was not soon over. If the Germans had done the vicious thing more thoroughly the war might have been over long ago.

God be thanked for German inefficiency. Since April, 1915, gas has been used constantly in various forms and ways by the Germans, and the Allies have not failed in reprisal. In fact, no doubt we shall soon be publicly informed of our contributions in this direction.

The enemy has had ample opportunity for years to realize that the American mind works in ton lots and not in pounds production, but he apparently did not grasp the big idea.

Some of the means adopted by our Allies and a few of our additions are current knowledge in technical circles, so no comfort can come to the enemy in indicating them to another group of readers.

Chemical Warfare Service

On our entrance into the war, the progressive policy of the Bureau of Mines at Washington, characteristic since its foundation, prompted it immediately to start its experts, who had been solving problems of mine gases, in a study of war gas.

Committees of the American Chemical Society and National Academy got many university and college laboratories busy. The Sanitary Corps of the Medical Department of the Army began work on defensive measures, while the Ordnance took up the matter of production of the offensive materials.

The Bureau of Mines established, in conjunction with the War Department, an elaborate experiment station in the buildings of the American University, where the Chemical Service Section, a newly established part of the Army, worked with civilian experts on research in finding new means of growing heads on the hydra, reputed to have been fathered by two well-known German chemists.

Over a thousand chemists, about half in uniform, were busy out in those woods near Washington. Experts from England (Major Auld especially) and France (Major Grignard and Lieutenant Engel) came over here and we sent some experienced chemical engineers over there.

Many people were anxious to be busy, some were anxiously busy, and some were plainly anxious because of duplication, lack of coordination, etc., in short, lost motion—a condition inevitable in view of the circumstances.

Now all this has been changed. The President by authority conferred by an Act of Congress, May, 1917, “to coordinate or consolidate ….. in the interest of economy and the more efficient concentration of the government,” ordered the organization of the Chemical Warfare Service, National Army, which was instructed to take over all the activities referred to above.

 Major-General William L. Sibert, the distinguished engineer, who was General Goethals’ right-hand associate in building the Panama Canal, and commander of the First Division of the Regular Army in France, was made director.

The General is a kindly wise giant of power and great strength. He uses few words and will have around him only those who can “deliver the goods.” He has already secured some of the best chemical talent in the United States, and there is no better elsewhere.

This new organization plans to have at least 2,500 officers and 20,000 selected enlisted men. It is rapidly rounding out. The General places production as the most important factor, but he recognizes the almost equal importance of having an adequate supply of the reserves.

The nature of what is going on in offensive and defensive gas warfare appears in the following classification, which, it must be understood, is not official:

  • Production in quantities of known poisonous or incapacitating substances to be used against the enemy.
  • Production of protective means in quantity to be used against toxic agencies by soldiers in the field and sailors in action.
  • Research on new incapacitating substances, and small units for quantity production of these novelties.
  • Research on improving the protective agencies to neutralize any unknown substance the enemy may spring.
  • Research on means for instantaneously detecting the presence of toxic substances coming from the enemy, that quick alarm may be given.
  • The maintenance of chemical industries and instruction in qualified institutions, where ample chemical reserves are to be trained not alone for warfare purposes, but for the industries and instructors for research and teaching as well.

It cannot fail to be a source of gratification to the American people to know that this program is proceeding at present in a most satisfactory manner, especially with emphasis on production of toxic agencies and means of protection. A limited discussion of some of these agencies and means is given below.

American Soldiers in France, Marching To the Front Wearing Gas Masks.

American Soldiers in France, Marching To the Front Wearing Gas Masks. French Pictorial Service. The American Review of Reviews, September 1918. GGA Image ID # 17fdf2fc7f

Gas Clouds

The first use of poison gas by the Germans was associated with trench warfare and depended upon the generation of a dense cloud of a heavy gas, which was intended to travel along with the wind, hugging the ground and falling into the trenches, where its work was mainly done.

In preparations for such an attack, cylinders weighing about ninety pounds, containing about forty pounds of the gas liquefied by pressure, were cached approximately every yard in the front trench opposite the position to be gassed.

Lead pipes were joined to the cylinders, led up over the top of the trench, bent into position, weighted, so that the exit was some distance away from the operator—pioneers, they were called.

Under favorable meteorological conditions, which were carefully determined in advance—a breeze blowing toward the enemy at a rate from four to eight miles per hour—the valves were opened so that the cylinders would be emptied in about three minutes.

Chlorine was used in places in such concentration that exposed metal parts were corroded, vegetation was bleached a mile away, and its serious effects upon domestic animals were noted several miles away.

It may be of interest to note favoritism in venom by calling attention to the fact that the Germans used poison gases primarily against the English and French Colonials and Russians at first.

Also it may be of equal interest to note that the British did not use gas in any form against the Turks at Gallipoli, although they had it there, and no doubt its use would have altered the outcome of that campaign. The Turks themselves have not used gas.

The element of surprise constitutes an important factor in such use of gas clouds, in fact in all phases of gas warfare. Against chlorine a simple protection was quickly devised, namely, a cloth hood, provided with goggles, which might readily he slipped over the head and be tucked under the shirt around the neck.

Before issuing, the hood was treated with a solution of soda and "hypo,” which neutralized the chlorine. It was another wonderful service of women in war—the making of 250,000 of those hoods by the women of Great Britain and getting them to France in a week! This means of protection long since became obsolete. The matter of defense is referred to more fully below.

A number of gas-cloud attacks were launched on the Western Front, but the casualties were probably much greater at each assault on the Russian Front, except the first time chlorine was used at Ypres, when 5,000 were killed and as many prisoners taken.

The Russians in many instances were never supplied with protective means of any kind, although Russian chemists later made some very valuable suggestions in selective defensive agents and devised some good masks.

Up to August, 1916, the Germans claimed to have killed nearly 50,000 by gas. No data as to total casualties are available. In this connection it may be said that chlorine alone was not the sole agent used.

Toward the end of 1915 about 20 per cent of phosgene (carbonyl chloride) was mixed with the chlorine. It is a more dangerous gas. because a comparatively slight gassing may show its fatal action only after several hours, when the soldier is out of the active zone.

Hand Grenades

Incidental to trench warfare the Germans developed hand grenades of glass and metal. They used them when on raids for clearing dug-outs and killing sappers.

The grenades were filled with such liquid chemicals as bromine (meaning stench), chlorsulphonic acid, etc.; all corrode the skin as a liquid, which fumes violently on exposure to the air, giving off suffocating and poisonous vapors.

Gas Shell

The use of gas shell was developed by the Germans soon after they applied the gas cloud. This gave an opportunity to use a variety of substances unsuitable for gas cloud, although chlorine and phosgene were also used in shell.

These two substances are liquid under pressure, as has been noted, and only a small powder charge was required to crack the shell when it reached its destination. The liquid immediately vaporized and produced a local cloud. The difference in sound as they burst made their detection easy.

The gas shell was extensively developed. Heavy corrosive liquids and even solids were charged into the shell provided with a high explosive, such as T. N. T., which on explosion by means of a suitable fuse, converted the liquid into a mist, or the solid was so finely pulverized as to become a dust cloud.

These particles of mist or dust were of such small size that it was intended that they should pass through pores of the protecting hood or mask then in use. They were also less reactive with the chemicals used in the first filters.

Furthermore, the mist would attach itself to the clothing or cling to the ground and slowly evolve poisonous or irritating vapors long after the gas shell bombardment had ceased. Men were thus poisoned by these delayed vapors sometime after the engagement.

American Troops Being Trained in the Use of Liquid Fire, One of the New Devices for Waging War.

American Troops Being Trained in the Use of Liquid Fire, One of the New Devices for Waging War. The Effect of the Liquid Fire Is Shown by the Flaming Trees and Hushes in the Line of Attack. Committee on Public Information. The American Review of Reviews, September 1918. GGA Image ID # 17fe8fa9ad


All the substances used were not necessarily of a poisonous nature, unless in great concentration. One class of these substances, known as "tear shell" or lachrymators, were among the first used by the Germans. They used this "T-Stoff” (xylyl and benzyl bromides) especially against the French in 1915.

One part in a million of air by-volume causes the eyes to so water as seriously to interfere with vision. Blindness, temporary, usually results from higher concentrations, which when very great produce nausea and vomiting.

Several other stoffs have been and are used; for example, “B-Stoff” (brominated methylethyl ketone), “Green T-Stoff” (a mixture of xylyl bromide and bromoacetone), each having particular tactical values, of which the limits of this article do not admit a discussion. The main purpose, however, is quite apparent.


When the Germans observed that the Allies were learning their game and their gas attacks were becoming less and less effective on account of the defensive means (masks) employed, they brought into play (1917) a “blue cross” (so marked) or “sneezing shell.”

This shell was filled with a solid (diphenylchlorarsine), mixed with a high explosive. The explosion was very similar to that of shrapnel or high explosive shell, which offer little or no damage from gas; only flying particles.

The fine powder not only affected the respiratory organs, but caused sneezing, involving such deep abdominal muscles as to provoke vomiting.

The evident purpose was to prevent the soldier from adjusting his mask or force him to remove it, if adjusted, only to be poisoned by the sneezing stuff (in great concentration) or by other gases which were discharged in the same area simultaneously.

Skin and Lung Corroding Chemicals

As already noted, the use of gas shell in their development gave wide range in employment of toxic substances in this chemical game of hide-and-seek. Poisonous liquids which would evolve a vapor from 3 to 6.6 times as heavy as the air were employed.

The liquids, or their mists, coming into contact with the skin, as the hands or the neck, would produce blisters and mean sores. Coming into contact with rubber, of which parts of the masks are composed, some of them render the rubber brittle and the mask becomes useless.

Absorbed in the clothing they penetrate to the skin, or may continue evolving poisonous fumes for a day or more. These liquids also wet the soil with which they come into contact. A soldier leaning against a sand bag, or sitting on the ground so wetted may thus unconsciously become affected.

One of these substances, of which there has been more or less publicity in the press, is called “mustard gas.” It is not in fact a gas at all, nor is it the real mustard oil, but a liquid (B B dichlorodiethyl sulphide), which gives off a vapor over live times as heavy as the air, with a faint garlic-like odor.

It is very characteristic in its action, its immediate effects being slight, with serious after-effects. In efforts to disguise its odor, in some cases a little prussic acid gas was mixed in; in other cases a solid (trioxymethylene) was added.

Some shell were marked with a yellow cross and called “yellow cross” shell. They contain “diphosgene” (trichloromethyl-chloroformate) mixed in varying proportions with chlorpicrin  (nitrochloroform) or other lachrymators. Soldiers were thus intended to weep at their own funerals.

Red Cross Shell

We have seen that the Germans devised different types of shell, containing weeping, or sneezing, or toxic substances. And we have seen that Kultur chose to designate some of them with the Cross—blue, yellow, and green crosses.

The climax of sardonic humor was reached when the Cross was further desecrated by applying the Red Cross as the sign on shell which contained a lachrymator, a sternutator, and a powerful poison as well. Perhaps these were really intended for the women, children, and infirm far behind the lines, for they too, even in the schools, are provided with protective means in France.

The amount of “gas" which may be sent over in the “shell” is limited and calls for an enormous number of shell in any extended action. It is reported that the Germans sent over one million gas shell within thirty days in a certain sector.

It is not inconceivable that the same number might be sent over to them in one day and be continued for thirty days or longer—what a stench scarred Germany would evolve!! 'Fliese are not nice words; they do not express sweet thoughts, but it’s the only spirit in which to fight such Godless vandals.

Research in Gas Warfare

Each of the substances mentioned and others used by the Hun, which have not been referred to, has its own characteristic physiological action that is taken advantage of in tactical application, involving primarily surprise.

All that is known to us is what has been learned through prodigious research of the chemists of the Allies and from captured documents. No hint as to retaliatory reprisals can appear, but some reference to means of defense evolved from elaborate research may in part he disclosed.

In bringing that phase of the subject to the attention of the reader it may not be amiss to say that it is an ill toxic substance that brings no good. Gaseous prussic acid has salvaged many fruit crops and rid many abodes and warehouses of cholera-carrying rats. So these toxic agents have in a measure rid many of the trenches of rats. Perhaps they may even yet rid the soldier, his dug-outs, rest billets, etc., of the “cooties."

When the inside history of the various phases of research in gas warfare, defensive and offensive, shall have been written, it will prove to be a document that would have caused Jules Verne to turn green with envy.

French Soldiers Wearing Gas Masks in the Front-Line Trenches.

French Soldiers Wearing Gas Masks in the Front-Line Trenches. Photograph by Kadel & Herbert. St. Nicholas Illustrated Magazine for Boys and Girls, August 1919. GGA Image ID # 17fee25c1f

Gas Defense

The heinous action of the Germans in using poison gases in contravention to all agreements naturally found the Allies unprepared for such criminal procedure.

Reference has already been made to the makeshift steps taken at first to meet the emergency. Once, however, it was recognized that the Germans meant to pursue such practices with utter abandon and apparently without restriction, the chemists of the Allies set about formulating the fundamental principles involved in the protection of troops against enemy gas attacks and the various procurement bureaux sought to provide the necessary’ equipment for each individual, for it had to assume a personal nature.

This resolved itself, first, in nullification, or purification, of the contaminated air the soldier was to breathe; and second, into elimination of accumulated gas in trenches, dug-outs, or topographic depressions in which the heavy poisonous air might accumulate.

In regard to the latter it is highly desirable to prevent the ingress of the gas. Such is quite out of the question in open trenches and valleys, but well-constructed dug-outs may he and are battened down with heavy blankets, which are kept wet, usually with solutions of chemicals.

The Germans sprinkled chloride of lime, or sprayed a water solution of that chemical, in trenches contaminated with “mustard gas.” This phase of the problem resolved itself into a matter of ventilation.

The contaminated atmosphere is removed by creating air currents by means of fires, or better by fanning or shoveling the air out of the trenches with large canvas fans or paddles—a suggestion of Lady Ayrton, who is a prominent physicist, as was also her late husband.

The efficiency of the ventilation is closely associated with the question of concentration of the contaminating gas and the specific physiological action of the toxic agent employed.

All poisons are harmless when in extreme dilution. The first dose under considerable dilution may exert decided physiological action.

The familiar events incident to the first cigar illustrate this. An individual becomes in time more or less immune, or partially so, as we know from the number of cigars smoked per day by many men.

So the soldier in time may become more or less immune to weak poisons and is not disturbed by breathing them.

We have thousands of instances of this daily among workmen in chemical factories. If we accumulate all the nicotine, tarry matters, and other products of combustion or solution from the ten cigars an inveterate smoker burns in a day and give it to him in one dose, down he goes. So it is with gas warfare.

Again there are certain poisons, as phosphorus, lead and carbon monoxide (a constituent of ordinary illuminating gas) which produce no serious lasting effects from one dose, even fairly concentrated; hut if the doses be repeated, even when very dilute, the poison, or its effects, accumulate with an inevitable result. Some of these war gases act in this way.

So as perfect elimination as possible of the toxic agent from the trenches, or other places to be occupied by troops, is of prime importance.

A Gas Mask Drill by United States Marines in France. Our Troops have Learned the Knack of Attaching the Masks in Record Time.

A Gas Mask Drill by United States Marines in France. Our Troops have Learned the Knack of Attaching the Masks in Record Time. Photo © Committee on Public Information. The American Review of Reviews, September 1918. GGA Image ID # 17ff624c57

Gas Masks

The purification of the air one is to breathe under such conditions of contamination involves filtration, which will remove by- physical or chemical means those substances which affect deleteriously the lungs or eyes, or both.

The filtering medium must protect against any concentration of the harmful substance liable to be met in the field, inclusive of unknown agents, which might be used by the enemy. The contrivance must fit so snugly that no air can enter except by passing through the filtering medium. It must be so constructed that it may he put on and adjusted in less than six seconds.

The filtering device (respirator) should be “fool proof" and not get out of order under the conditions of trench or open warfare. Its adjustment must be so simple that the uneducated soldier, or a child, can learn to use it quickly and properly. For the soldier, its weight should be reduced to the minimum and its design such that his movements maybe incommoded as little as possible.

That was not an easy job for the researcher. In fact, he has not yet secured all the desiderata, but at least he has provided a mask which protects, saves lives and still presents a fighting man active and vigorous, harmless amidst all the German gas, but his burden is great.

So far the remarkable million athletes in the line in France and other countries from our country have been of such superior physique that they have borne the extra burden, but not without discomfort.

It is no criticism of our bed-fellow Allies to say that the first million the United States put into the field in France was the finest body of men, physically and morally, ever collected for war purposes in the history- of the world, because we had the benefit of the experience of all nations to guide us, a wonderful virile people to draw from, and the fundamental principle of democracy to rely upon in its construction.

Withal, we were crude soldiers, to be sure, as we had not the experience. However, we had the material; our medical men knew how to conserve it ; we were able to feed it right : our Allies taught eager students ways of modern fighting only.

All the air breathed is taken in through the mouth. The nostrils are closed with a mechanical device, else a defect in the fabric of the mask, perhaps a hole or rip produced in the rough handling incident to front line service, might allow the breathing of unfiltered air.

The inspired air is drawn through a canister, containing certain chemicals which absorb, destroy, or neutralize the toxic agents. It then passes through a flexible tube and mouthpiece very similar to the mouthpiece of a football nose guard. The expired air passes out through a valve, which automatically closes during inspiration.

It has long been known that charcoal absorbs various gases to different degrees. The absorptive value depends upon the character of the carbon and the means by which the charcoal is produced.

Pure research on the rare gases of the atmosphere some years ago showed that charcoal made from cocoanut shells possessed unusual absorptive values.

So charcoal is made from cocoanut shells, the seed of peaches and apricots, as well as ivory nut. then granulated to definite sizes and mixed with granules of especially prepared chemicals, which react with the objectionable gases, in proportions that have been carefully determined.

This mixture is placed in specially designed canisters (filters), which are attached to the flexible intake tube referred to. The masks are provided with non-shattering goggles, so constructed as not to be dimmed by condensing moisture from a perspiring face and providing considerable freedom of vision that the soldier may use his rifle or attend his duties, if he be in the artillery, for example.

A Gas Storm Coming Up Over the American Trenches. Committee of Public Information. St. Nicholas Magazine, August 1919.

A Gas Storm Coming Up Over the American Trenches. Committee of Public Information. St. Nicholas Magazine, August 1919. GGA Image ID # 17ff14e503

The efficiency of any filter depends upon the fineness of the pores of the filtering medium. Chemical action, which is partly essential in destroying the toxic bodies, depends upon intimacy of contact of the agents involved. So the smaller the pores, all other matters being equal, the purer is the air breathed.

These interstices, however, may be so small as to place too heavy a burden upon the breathing apparatus of the individual, so the soldier gets insufficient air, especially under the active physical exertion during a battle.

That means the production of incomplete oxidation products in the body, which, as they accumulate, induce abnormal fatigue, that is to be avoided.

Good solutions, if not the ideal, have been worked out by our chemists and physiologists, so one may understand what is really going on when he observes, in certain places in the United States, a group of soldiers, disguised with gas masks to resemble ant-eaters, engaging in a double quick or playing a game of baseball in such array.

The game is complete in every particular, with umpires and side line coaches, for officers must wear the masks and give commands; the signal corps and others using the telephone must also have their protection.

Protection of Animals

In the prosecution of the research, in both offensive and defensive gas warfare, it has of course been necessary to make many animal experiments.

These had to do not only with human beings, but were concerned as well with the conservation of our so-called dumb allies, horses, mules, donkeys, carrier pigeons, and dogs.

British Gas Masks for Horses and Men

British Gas Masks for Horses and Men, Photo © Kadel & Herbert. St. Nicholas Magazine, August 1919. GGA Image ID # 17ff21b829

It appears only necessary to protect horses and mules from the toxic agents; dogs and carrier pigeons must also be protected from tear gases. All have been provided for with special masks.

The mule takes less kindly to the new accouterment than the others. The donkey is more amenable, for the “California Canary” having involuntarily ceased to sing is docile enough.

No such disaster as that experienced by the Canadians and Turcos at Ypres, the Russians in the Carpathians, or the Italians near Trieste menaces our fine boys or the Allies anywhere now.

Many, many thousands of these protective agencies—ample— are being made, inspected with the utmost care daily, and are being sent “over there.”

The production goes forward ; the research must continue. These researches have so far served well to correct the abuse of research indulged in by the Germans.

Chas. Baskerville, Ph. D., F. C. S., "Chemical Warfare - 'Gas' In This War," in American Review of Reviews, New York:The Review of Reviews Co., Vol. 58, September 1918, pp. 273-280.

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