CHAPTER III

DEVELOPMENT OF THE CHEMICAL WARFARE SERVICE

Modern chemical warfare dates from April 22, 1915. Really, however, it may be said to have started somewhat earlier, for Germany undoubtedly had spent several months in perfecting a successful gas cylinder and a method of attack. The Allies, surprised by such a method of warfare, were forced to develop, under pressure, a method of defense, and then, when it was finally decided to retaliate, a method of gas warfare. “Offensive organizations were enrolled in the Engineer Corps of the two armies and trained for the purpose of using poisonous gases; the first operation of this kind was carried out by the British at the battle of Loos in September, 1915.

“Shortly after this the British Army in the field amalgamated all the offensive, defensive, advisory and supply activities connected with gas warfare and formed a ‘Gas Service’ with a Brigadier General as Director. This step was taken almost as a matter of necessity, and because of the continually increasing importance of the use of gas in the war (Auld).”

At once the accumulation of valuable information and experience was started. Later this was very willingly and freely placed at the disposal of American workers. Too much cannot be said about the hearty co-operation of England and France. Without it and the later exchange of information on all matters regarding gas warfare, the progress of gas research in all the allied countries would have been very much retarded.

While many branches of the American Army were engaged in following the progress of the war during 1915-1916, the growing importance of gas warfare was far from being appreciated. When the United States declared war on Germany April 6, 1917, there were a few scattered observations on gas warfare in various offices of the different branches, but there was no attempt at an organized survey of the field, while absolutely no effort had been made by the War Department to inaugurate research in a field that later had 2,000 men alone in pure research work. Equally important was the fact that no branch of the Service had any idea of the practical methods of gas warfare.

The only man who seemed to have the vision and the courage of his convictions was Van H. Manning, Director of the Bureau of Mines. Since the establishment of the Bureau in 1908 it had maintained a staff of investigators studying poisonous and explosive gases in mines, the use of self-contained breathing apparatus for exploring mines filled with noxious gases, the treatment of men overcome by gas, and similar problems. At a conference of the Director of the Bureau with his Division Chiefs, on February 7, 1917, the matter of national preparedness was discussed, and especially the manner in which the Bureau could be of most immediate assistance with its personnel and equipment. On February 8, the Director wrote C. D. Walcott, Chairman of the Military Committee of the National Research Council, pointing out that the Bureau of Mines could immediately assist the Navy and the Army in developing, for naval or military use, special oxygen breathing apparatus similar to that used in mining. He also stated that the Bureau could be of aid in testing types of gas masks used on the fighting lines, and had available testing galleries at the Pittsburgh experiment station and an experienced staff. Dr. Walcott replied on February 12 that he was bringing the matter to the attention of the Military Committee.

A meeting was arranged between the Bureau and the War College, the latter organization being represented by Brigadier General Kuhn and Major L. P. Williamson. At this conference the War Department enthusiastically accepted the offer of the Bureau of Mines and agreed to support the work in every way possible.

The supervision of the research on gases was offered to Dr. G. A. Burrell, for a number of years in charge of the chemical work done by the Bureau in connection with the investigation of mine gases and natural gas. He accepted the offer on April 7, 1917. The smoothness with which the work progressed under his direction and the importance of the results obtained were the result of Colonel Burrell’s great tact, his knowledge of every branch of research under investigation and his imagination and general broad-mindedness.

Once, however, that the importance of gas warfare had been brought to the attention of the chemists of the country, the response was very eager and soon many of the best men of the university and industrial plants were associated with Burrell in all the phases of gas research. The staff grew very rapidly and laboratories were started at various points in the East and Middle West.

It was immediately evident that there should be a central laboratory in Washington to co-ordinate the various activities and also to considerably enlarge those activities under the joint direction of the Army, the Navy and the Bureau of Mines. Fortunately a site was available for such a laboratory at the American University, the use of the buildings and grounds having been tendered President Wilson on April 30, 1917. Thus originated the American University Experiment Station, later to become the Research Division of the Chemical Warfare Service.

Meanwhile other organizations were getting under way. The procurement of toxic gases and the filling of shell was assigned to the Trench Warfare Section of the Ordnance Department. In June, 1917, General Crozier, then Chief of the Ordnance Department, approved the general proposition of building a suitable plant for filling shell with toxic gas. In November, 1917, it was decided to establish such a plant at Gunpowder Neck, Maryland. Owing to the inability of the chemical manufacturers to supply the necessary toxic gases, it was further decided, in December, 1917, to erect at the same place such chemical plants as would be necessary to supply these gases. In January, 1918, the name was changed to Edgewood Arsenal, and the project was made a separate Bureau of the Ordnance Department, Col. William H. Walker, of the Massachusetts Institute of Technology, being soon afterwards put in command.

While, during the latter part of the War, gas shell were handled by the regular artillery, special troops were needed for cylinder attacks, Stokes’ mortars, Livens’ projectors and for other forms of gas warfare. General Pershing early cabled, asking for the organization and training of such troops, and recommended that they be placed, as in the English Army, under the jurisdiction of the Engineer Corps. On August 15, 1917, the General Staff authorized one regiment of Gas and Flame troops, which was designated the “30th Engineers,” and was commanded by Major (later Colonel) E. J. Atkisson. This later became the First Gas Regiment, of the Chemical Warfare Service.

About this time (September, 1917) the need of gas training was recognized by the organization of a Field Training Section, under the direction of the Sanitary Corps, Medical Department. Later it was recognized that neither the Training Section nor the Divisional Gas Officers should be under the Medical Department, and, in January, 1918, the organization was transferred to the Engineer Corps.

All of these, with the exception of the Gas and Flame regiment, were for service on this side. The need for an Overseas force was recognized and definitely stated in a letter, dated August 4, 1917. On September 3, 1917, an order was issued establishing the Gas Service, under the command of Lt. Col. (later Brigadier General) A. A. Fries, as a separate Department of the A. E. F. in France. In spite of a cable on September 26th, in which General Pershing had said

“Send at once chemical laboratory, complete equipment and personnel, including physiological and pathological sections, for extensive investigation of gases and powders....”

it was not until the first of January, 1918, that Colonel R. F. Bacon of the Mellon Institute sailed for France with about fifty men and a complete laboratory equipment.

Meantime a Chemical Service Section had been organized in the United States. This holds the distinction of being the first recognition of chemistry as a separate branch of the military service in any country or any war. This was authorized October 16, 1917, and was to consist of an officer of the Engineers, not above the rank of colonel, who was to be Director of Gas Service, with assistants, not above the rank of lieutenant colonel from the Ordnance Department, Medical Department and Chemical Service Section. The Section itself was to consist of 47 commissioned and 95 non-commissioned officers and privates. Colonel C. L. Potter, Corps of Engineers, was appointed Director and Professor W. H. Walker was commissioned Lieutenant Colonel and made Assistant Director of the Gas Service and Chief of the Chemical Service Section. This was increased on Feb. 15, 1918 to 227 commissioned and 625 enlisted men, and on May 6, 1918 to 393 commissioned and 920 enlisted men. Meanwhile Lt. Col. Walker had been transferred to the Ordnance and Lt. Col. Bogert had been appointed in his place.

At this time practically every branch of the Army had some connection with Gas Warfare. The Medical Corps directed the Gas Defense production. Offense production was in the hands of the Ordnance Department. Alarm devices, etc., were made by the Signal Corps. The Engineers contributed their 30th Regiment (Gas and Flame) and the Field Training Section. The Research Section was still in charge of the Bureau of Mines, in spite of repeated attempts to militarize it. And in addition, the Chemical Service Section had been formed primarily to deal with overseas work. While the Director of the Gas Service was expected to co-ordinate all these activities, he was given no authority to control policy, research or production.

In order to improve these conditions Major General Wm. L. Sibert, a distinguished Engineer Officer who built the Gatun Locks and Dam of the Panama Canal and who had commanded the First Division in France, was appointed Director of the Chemical Warfare Service on May 11, 1918. Under his direction the Chemical Warfare Service was organized with the following Divisions:

Overseas Brigadier General Amos A. Fries Research Colonel G. A. Burrell Development Colonel F. M. Dorsey Gas Defense Production Colonel Bradley Dewey Gas Offense Production Colonel Wm. H. Walker Medical Colonel W. J. Lyster Proving Lt. Col. W. S. Bacon Administration Brigadier General H. C. Newcomer Gas and Flame Colonel E. J. Atkisson

The final personnel authorized, though never reached owing to the signing of the Armistice, was 4,066 commissioned officers and 44,615 enlisted men; this was including three gas regiments of eighteen companies each.

General Sibert brought with him not only an extended experience in organizing and conducting big business, but a strong sympathy for the work and an appreciation of the problem that the American Army was facing in France. He very quickly welded the great organization of the Chemical Warfare Service into a whole, and saw to it that each department not only carried on its own duties but co-operated with the others in carrying out the larger program, which, had the war continued, would have beaten the German at his own game.

More detailed accounts will now be given of the various Divisions of the Chemical Warfare Service.

ADMINISTRATION DIVISION

The Administration Division was the result of the development which has been sketched in the preceding pages. It is not necessary to review that, but the organization as of October 19, 1918 will be given:

Director Major General Wm. L. Sibert Staff: Medical Officer Colonel W. J. Lyster Ordnance Officer Lt. Col. C. B. Thummel British Military Mission Major J. H. Brightman Assistant Director Colonel H. C. Newcomer Office Administration Major W. W. Parker Relations Section Colonel M. T. Bogert Personnel Section Major F. E. Breithut Contracts and Patents Section Captain W. K. Jackson Finance Section Major C. C. Coombs Requirements and Progress Section Capt. S. M. Cadwell Confidential Information Section Major S. P. Mullikin Transportation Section Captain H. B. Sharkey Training Section Lt. Col. G. N. Lewis Procurement Section Lt. Col. W. J. Noonan

The administrative offices were located in the Medical Department Building. The function of most of the sections is indicated by their names.

The Industrial Relations Section was created to care for the interests of the industrial plants which were considered as essential war industries. Through its activity many vitally important industries were enabled to retain, on deferred classification or on indefinite furlough, those skilled chemists without which they could not have maintained a maximum output of war munitions.

In the same way the University Relations Section cared for the educational and research institutions. In this way our recruiting stations for chemists were kept in as active operation as war conditions permitted.

Another important achievement of the Administration Section was to secure the order from The Adjutant General, dated May 28, 1918, that read:

“Owing to the needs of the military service for a great many men trained in chemistry, it is considered most important that all enlisted men who are graduate chemists should be assigned to duty where their special knowledge and training can be fully utilized.

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“Enlisted men who are graduate chemists will not be sent overseas unless they are to be employed on chemical duties....”

While this undoubtedly created a great deal of feeling among the men who naturally were anxious to see actual fighting in France, it was very important that this order be carried out in order to conserve our chemical strength. The following clipping from the September, 1918, issue of _The Journal of Industrial and Engineering Chemistry_ shows the result of this order.

“CHEMISTS IN CAMP

“As the result of the letter from The Adjutant General of the Army, dated May 28, 1918, 1,749 chemists have been reported on. Of these the report of action to August 1, 1918, shows that 281 were ordered to remain with their military organization because they were already performing chemical duties, 34 were requested to remain with their military organization because they were more useful in the military work which they were doing, 12 were furloughed back to industry, 165 were not chemists in the true sense of the word and were, therefore, ordered back to the line, and 1,294 now placed in actual chemical work. There were being held for further investigation of their qualifications on August 1, 1918, 432 men. The remaining 23 men were unavailable for transfer, because they had already received their overseas orders.

“The 1,294 men, who would otherwise be serving in a purely military capacity and whose chemical training is now being utilized in chemical work, have, therefore, been saved from waste.

“Each case has been considered individually, the man’s qualifications and experience have been studied with care, the needs of the Government plants and bureaus have been considered with equal care, and each man has been assigned to the position for which his training and qualifications seem to fit him best.

“Undoubtedly, there have been some cases in which square pegs have been fitted into round holes, but, on the whole, it is felt that the adjustments have been as well as could be expected under the circumstances.”

RESEARCH DIVISION

The American University Experiment Station, established by the Bureau of Mines in April, 1917, became July 1, 1918 the Research Division of the Chemical Warfare Service. For the first five months work was carried out in various laboratories, scattered over the country. In September, 1917, the buildings of the American University became available; a little later portions of the new chemical laboratory of the Catholic University, Washington, were taken over. Branch laboratories were established in many of the laboratories of the Universities and industrial plants, of which Johns Hopkins, Princeton, Yale, Ohio State, Massachusetts Institute of Technology, Harvard, Michigan, Columbia, Cornell, Wisconsin, Clark, Bryn Mawr, Nela Park and the National Carbon Company were active all through the war.

At the time of the signing of the armistice the organization of the Research Division was as follows:

Col. G. A. Burrell Chief of Research Division Dr. W. K. Lewis In Charge of Defense Problems Dr. E. P. Kohler[5] In Charge of Offense Problems Dr. Reid Hunt Advisor on Pharmacological Problems Lt. Col. W. D. Bancroft In Charge of Editorial Work and Catalytic Research Lt. Col. A. B. Lamb[6] In Charge of Defense Chemical Research Dr. L. W. Jones[7] In Charge of Offense Chemical Research Major A. C. Fieldner In Charge of Gas Mask Research Major G. A. Richter In Charge of Pyrotechnic Research Capt. E. K. Marshall[8] In Charge of Pharmacological Research Dr. A. S. Loevenhart[9] In Charge of Toxicological Research Major R. C. Tolman In Charge of Dispersoid Research Major W. S. Rowland[10] In Charge of Small Scale Manufacture Major B. B. Fogler[11] In Charge of Mechanical Research and Development Captain G. A. Rankin In Charge of Explosive Research Major Richmond Levering In Charge of Administration Section

[Footnote 5: Succeeded Dr. John Johnson who went to the National Research Council.]

[Footnote 6: At first Lt. Col. J. F. Norris was in charge of all chemical research. About December, 1917, it was divided into Offense and Defense, and Lt. Col. Lamb was placed in charge of Defense. When Col. Norris went to England as Liaison Officer, Dr. Jones took his place.]

[Footnote 7: At first Lt. Col. J. F. Norris was in charge of all chemical research. About December, 1917, it was divided into Offense and Defense, and Lt. Col. Lamb was placed in charge of Defense. When Col. Norris went to England as Liaison Officer, Dr. Jones took his place.]

[Footnote 8: At first Lt. Col. J. F. Norris was in charge of all chemical research. About December, 1917, it was divided into Offense and Defense, and Lt. Col. Lamb was placed in charge of Defense. When Col. Norris went to England as Liaison Officer, Dr. Jones took his place.]

[Footnote 9: In the early organization of the Bureau of Mines, Dr. Yandall Henderson was in charge of the Medical Sciences. Associated with him were Dr. F. P. Underhill, in charge of Therapeutic Research; Major M. C. Winternitz, in c of Pathological Research and Captain E. K. Marshall in charge of Pharmacological Research. About May 1, 1918, Pharmacological Research became so extensive that the Section was made into two, with Marshall and Loevenhart in charge, while Dr. Hunt was appointed special adviser on pharmacological problems. When the transfer to the War Department was made, Henderson, Underhill, Winternitz and Marshall were transferred to the Medical Division.]

[Footnote 10: Lt. Col. McPherson was formerly in charge, and was later transferred to Ordnance.]

[Footnote 11: This Section was originally under H. H. Clark. Later it was split into two, with Clark and Fogler in charge, and finally consolidated under Fogler.] The chief functions of the Research Division were:

1. To prepare and test compounds which might be of value in gas warfare, determining the properties of these substances and the conditions under which they might be effective in warfare.

2. To develop satisfactory methods of making such compounds as seemed promising (Small Scale).

3. To develop the best methods of utilizing these compounds.

4. To develop materials which should absorb or destroy war gases, studying their properties and determining the conditions under which they might be effective.

5. To develop satisfactory methods of making such absorbents as might seem promising.

6. To develop masks, canisters, protective clothing, etc.

7. To develop incendiaries, smokes, signals, etc., and the best methods of using the same.

[Illustration: FIG. 4.—American University Experiment Station, showing Small Scale Plants.]

8. To co-operate with the manufacturing divisions in regard to difficulties arising during the operations of manufacturing war gases, absorbents, etc.

9. To co-operate with other branches of the Government, civil and military, in regard to war problems.

10. To collect and make available to the Director of the Chemical Warfare Service all information in regard to the chemistry of gas warfare.

The relation of the various sections may best be shown by outlining the general procedure used when a new toxic substance was developed.

The substance in question may have been used by the Germans or the Allies; it may have been suggested by someone outside the station; or the staff may have thought of it from a search of the literature, from analogy or from pure inspiration. The Offense Research Section made the substance. If it was a solid it was sent to the Dispersoid Section, where methods of dispersing it were worked out. When this had been done, or, at once, if the compound was a liquid or vapor, it was sent to the Toxicological Section to be tested for toxicity, lachrymatory power, vesicant action, or other special properties. If these tests proved the compound to have a high toxicity or a peculiar physiological behavior, it was then turned over to a number of different sections.

The Offense Research Section tried to improve the method of preparation. When a satisfactory method had been found, the Chemical Production or Small Scale Manufacturing Section endeavored to make it on a large scale (50 pounds to a ton) and worked out the manufacturing difficulties. If further tests showed that the substance was valuable, the manufacture was then given to the Development Division or the Gas Offense Production Division for large scale production.

Meanwhile the Analytical Section had been working on a method for testing the purity of the material and for analyzing air mixtures, and the Gas Mask Section had run tests against it with the standard canisters. If the protection afforded did not seem sufficient, the Defense Chemical Section studied changes in the ingredients of the canister or even developed a new absorbent or mixture of absorbents to meet the emergency. If a change in the mechanical construction of the canister was necessary, this was referred to the Mechanical Research Section; this work was especially important in case the material was to be used as a toxic smoke.

The compound was also sent to the Pyrotechnic Section, which studied its behavior when fired from a shell, or, if suitable, when used in a cylinder. If it proved stable on detonation, large field tests were then made by the Proving Division, in connection with the Pyrotechnic and Toxicological Sections of the Research Division, to learn the effect when shell loaded with the compound were fired from guns on a range, with animals placed suitably in or near the trenches. The Analytical Section worked out methods of detecting the gas in the field, wherever possible.

The Medical Division, working with the Toxicological and Pharmacological Sections, studied pathological details, methods of treating gassed cases, the effect of the gas on the body, and in some cases even considered other questions, such as the susceptibility of different men.

If the question of an ointment or clothing entered into the matter of protection, these were usually attacked by several Sections from different points of view.

Out of the 250 gases prepared by the Offense Chemical Research Section, very few were sufficiently valuable to pass all of these tests and thus the number of gases actually put into large scale production were less than a dozen. This had its advantages, for it made unnecessary a large number of factories and the training of men in the manufacturing details of many gases. As one British report stated, “The ultimate object of chemical warfare should be to produce two substances only; one persistent and the other non-persistent; both should be lethal and both should be penetrants.” They might well have added that both should be instantly and powerfully lachrymatory.

Since most of the work of the Research Division will be covered in detail in later chapters, only a brief summary of the principal problems will be given here.

The first and most important problem was the development of a gas mask. This was before Sections had been organized and was the work of the entire Division. After comparing the existing types of masks it was decided that the Standard Box Respirator of the British was the best one to copy. Because we were entirely new at the game that meant work on charcoal, soda-lime, and the various mechanical parts of the mask, such as the facepiece, elastics, eyepieces, mouthpiece, noseclip, hose, can, valves, etc. The story of the “first twenty thousand” is very well told by Colonel Burrell.[12]

[Footnote 12: _J. Ind. Eng. Chem._, =11=, 93 (1919).]

“THE FIRST TWENTY THOUSAND

“About the first of May, 1917, Major L. P. Williamson,

## acting as liaison officer between the Bureau of

Mines and the War Department, put the last ounce of ‘pep’ into the organization by asking us to build 20,000 gas masks for shipment overseas. 20,000 masks did not seem like a very large order. We did not fully appreciate all the conditions which a war gas mask had to encounter, so we readily and willingly accepted the order. Then began a struggle with can manufacturers, buckle makers, manufacturers of straps, rubber facepieces, eyepieces, knapsacks, etc. The country was canvassed from the Atlantic Coast to the Mississippi River for manufacturers who could turn out the different parts acceptably and in a hurry.

“Charcoal was made from red cedar by the Day Chemical Co. of Westline, Pennsylvania; soda-lime permanganate was manufactured by the General Chemical Company; knapsacks by the Simmons Hardware Company in St. Louis; facepieces by the Goodrich and Goodyear Rubber Companies at Akron; canisters by the American Can Company; and the assembly made at one of the plants of the American Can Company in Long Island City.

“The writer cannot recall all the doubts, fears, optimism, and enthusiasm felt in turn by different members of the organization during the fabrication of those first 20,000 masks. We were performing an important task for the War Department. Night became day. Dewey, Lewis, Henderson, Gibbs, and others stepped from one train to another, and we used the telephone between Washington and St. Louis or Boston as freely as we used the local Washington telephone.

“We thought we could improve on the English box respirator on various points. We made the canister larger, and have been glad ever since that we did. We thought the English mouthpiece was too flexible and too small, and made ours stiff and larger, and were sorry we made the change. We tested the fillings against chlorine, phosgene, prussic acid, etc., and had a canister that was all that was desired for absorbing these gases. But, alas, we did not know that chloropicrin was destined to be one of the most important war gases used by the various belligerents. Further, it was not fully appreciated that the rubberized cloth used in making the facepiece had to be highly impermeable against gases, that hardness as much as anything else was desired in the make-up of the soda-lime granules in order to withstand rough jolting so that the fines would not clog the canister, and raise the resistance to breathing to a prohibitive figure. Neither was it appreciated at that time by any of the allies, that the gas mask really should be a be a fighting instrument, one that men could work hard in, run in, and wear for hours, without too serious discomfort.

“The first 20,000 masks sent over to England were completed by the Research Division in record time. As compared with the French masks, they were far superior, giving greater protection against chlorine, phosgene, superpalite, prussic acid, xylyl bromide, etc. The French mask was of the cloth type, conforming to the face, and consisting of twenty layers of cheesecloth impregnated with sodium phenate and hexamethylenetetramine. Chloropicrin went through this like a shot. Just before the masks were sent abroad, we received disturbing rumors of the contemplated use of large quantities of chloropicrin. The French, apparently, had no intention of changing the design of their mask, and did not do so for months to come. We therefore released the masks, they were sent abroad, and an anxious research group on this side of the water waited expectantly for the verdict. It came. A brief cablegram told us what our English cousins thought of us. It was a subject they had been wrestling with for two years and a half. They had had battlefield experience; they had gone through the grief of developing poor masks into better ones, knew the story better than we did, and after a thorough test ‘hammered’ the American design unmercifully.

“This experience put the Research Division on its mettle. Our first attempt had given us the necessary preliminary experience; cablegrams and reports traveled back and forth; an expert or two eventually came to this country from England in response to previous appeals for assistance, and we turned with adequate information to the development of a real mask.”

The story of mustard gas is given later. It probably occupied more time and thought on the part of the Research Division, as well as that of Edgewood Arsenal and the Development Division, than any other gas.

Diphenylchloroarsine led to the preparation of a series of arsenic compounds, some more easily prepared and more or less effective.

Cyanogen chloride and cyanogen bromide, reported by the Italians as having been used by the Germans, were extensively studied.

The Inorganic Section was early interested in special incendiary materials which were developed for bombs, shells, darts and grenades, and which were later taken over by the Pyrotechnic Section, and finally adopted by the Ordnance Department.

In discussing the work one can very well start with the Offense Section. This Section had two aims in view always, to develop methods of making the gases used by the Germans more economically than they were making them, and to develop better gases if possible. When we entered the war, chlorine, phosgene and chloropicrin were the lethal gases used, while bromoacetone and xylyl bromide were the lachrymators. It was not a difficult matter to prepare these. But the introduction of mustard gas in the summer of 1917 and of diphenylchloroarsine in the autumn of the same year, not only made our chemists ponder over a manufacturing method, but also so revised our notions of warfare that the possibility of using other substances created the need for extensive research. The development of bromobenzylcyanide by the French likewise opened a new field among lachrymatory substances.

Colored rockets and smokes were developed for the Navy and Army. The smoke box was also studied but the work was taken over by the Pyrotechnic Section.

A large amount of pure inorganic research on arsine and arsenides, fluorine, hydrofluoric acid and fluorides, cyanides, cyanogen sulfide and nitrogen tetroxide was carried out, sometimes successfully and at other times with little or no success.

The Analytical Section not only carried out all routine analyses but developed methods for many new gases.

The Offense Section worked in very close contact with the Small Scale Manufacturing Section (Chemical Production Section). Often it happened that a method, apparently successful in the laboratory, was of no value in the plant. Small scale plants were developed for mustard gas, hydrocyanic acid, cyanogen chloride, arsenic trichloride, arsenic trifluoride, magnesium arsenide, superpalite and bromobenzylcyanide.

The Chemical Defense Section, organized January, 1918, was occupied with problems relating to protection, such as charcoal, soda-lime, and special absorbents, eyepieces, smoke filters, efficiency of absorbents, and special work with mustard gas.

Charcoal demanded extensive research. Raw materials required a world-wide search, carbonizing methods had to be developed, and impregnating agents were thoroughly studied. This story is told in

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