Mustard gas

“ When one considers the high boiling point of mustard gas, and its consequent low vapor pressure, he is likely to conclude that such a substance would be of comparatively little value as a toxic or poison gas. While it is true that an important part of the military value of mustard gas has been because of its vesicant properties, the fact still remains that it is one of our most toxic war gases. ”

“ Mustard gas, as is well known, is effective in extremely low concentrations and has very great persistency. In dry warm weather mustard gas, scattered on the ground and shrubbery, will not be fully evaporated for two to three days and accordingly will give off vapors that not only burn the lungs and eyes but the soft, moist parts of the skin as well. In cool, damp weather the gas remains in dangerous quantity for a week and occasionally longer. ”

“ Every worker who has worked with mustard gas has noticed that some individuals are much more susceptible to skin burns from this substance than are others. Marshall made a study of 1282 men at Edgewood Arsenal, using a 1 per cent and a 0.01 per cent solution of mustard gas in paraffin oil. ”

“ The large number of casualties in connection with the manufacture of mustard gas made it imperative that the workmen be protected not only from splashes of the liquid mustard gas, but also from its vapors. ”

“ The gas itself rapidly penetrates clothing and burns the skin even when the concentration of the gas is very low. Probably the majority of burns from mustard gas arose from concentrations of gas consisting of less than one part of gas to five hundred thousand of air. Furthermore, the gas is fully fifty per cent cumulative in its effects, that is, in extremely low concentrations over a period of hours it will produce more than fifty per cent the effect that a far higher concentration would produce in a relatively shorter time. ”

“ The second gas was dichloroethyl sulfide, mustard gas, Yellow Cross or Yperite. Mustard gas, as it is commonly designated, is probably the most important single poisonous substance used in gas warfare. It was first used by the Germans at Ypres, July 12, 1917. The amount of this gas used is illustrated by the fact that at Nieuport more than 50,000 shell were fired in one night, some of which contained nearly three gallons of the liquid. ”

“ Since mustard gas has a greatly delayed action it was found that if men who had been exposed to it could be given a thorough bath with soap and water within a half hour or even a full hour, the mustard gas burns would be prevented or very greatly reduced in severity. ”

“ Certain sulfonated oils accelerate the rate of hydrolysis, both by increasing the rate of solution and the solubility of the mustard gas. Alkalies also increase the rate of hydrolysis. Oxidizing agents destroy mustard gas. This reaction was made use of practically in that solid bleaching powder was early introduced as a means of destroying mustard gas in the field. ”

“ Unsolved Problems of Mustard Gas.—The use of a chemical which attacks some unexpected human function introduces many disturbing and disorganising factors. Thus the introduction of mustard gas has left us with a number of unsolved problems. By employing this substance Germany departed from her usual caution and violated one of the first principles of chemical warfare. It is unsound for any nation to introduce a new weapon, unless that nation is, itself, furnished with the means of protection against its eventual employment by the enemy. ”

“ It will thus be seen that for a persistent gas, though not deadly poisonous, mustard gas is a nasty proposition. First the gas does not of itself force a man to protect himself. With the old lachrymators a man either put on his mask or his eyes would smart and water so badly that he could not keep them open. ”

“ The killing gases were phosgene, chlorpicrin, and chlorine. Mustard gas in sufficient amount was also fatal, its effect being identical to that of a deep burn. It attacked the lungs, the eyes, the skin, and even the intestines if food contaminated with mustard gas were swallowed. An insidious feature of mustard gas is the fact that its action is practically always delayed. It might be several hours after a man was gassed, even fatally, with mustard before he became aware of it, and then it was too late to administer the treatment that might save his life. ”

“ While with practically all gases except mustard gas a man is comparatively safe while breathing a concentration very noticeable to the sense of smell, the only safe rule with mustard gas is to consider as dangerous any concentration that can be smelled. ”

“ Hirt, Strasbourg tells me:
“Mustard gas in a dilution of 1:100 is dangerous to human beings if it contacts the body in an adequate amount. Above all, mustard gas is dangerously effective to clothing, as is known, even when greatly diluted, especially in connection with dampness. Mustard gas touching the skin even in a dilution of 1:100 causes reddening, possibly it causes little cysts without effecting necrosis. That is, the effect is much weaker than that of pure mustard gas. ”

“ Thus the German mustard gas has a mustard smell, while the Allies mustard gas, due to a slight difference in the method of manufacture, has a very perfect garlic odor. Not only must officers and men who handle gas training know the smell of the various gases, but they must know when the concentration of each is high enough to be dangerous. ”

“ Due to the rapid evaporation of the non-persistent gases they are used generally only in dense clouds, whether those clouds be produced from cylinders or from bombs. These gases are used only for producing immediate casualties, as the necessary amount of gas to force the enemy to constantly wear his mask by the use of non-persistent gases alone could not possibly be taken to the front. [Pg 390]
Mustard gas, which is highly persistent and also attacks the lungs, eyes and skin of the body, may and will be used to force the wearing of the mask. ”

“ Take it altogether, Yellow Cross gas is very much more than an annoyance, but there is no question that good discipline and thorough appreciation and carrying out of the orders laid down for the protection of troops have reduced the losses in very much [179] the same way that the screwed-up discipline reduced the losses after the first introduction of Green Cross Shell. One of the most objectionable features of the mustard gas is the continual care that has to be exercised to prevent casualties. ”

“ With phosgene and similar non-persistent gases that volatilize almost completely upon the burst of the shell it is necessary to build up a high concentration immediately. The exact opposite is true of mustard gas. Mustard gas can be fired very slowly with the certain knowledge that all shells fired [Pg 178] at one moment will be effective when the next is fired, though twelve hours or more may intervene between the first and last firing. Thus, while with phosgene a large number of guns are needed for a gas attack, with mustard gas the number can be reduced to one-tenth or even less. ”

“ At that time the Germans heavily shelled with mustard gas four or five small woods and two or three villages. It was necessary for the men to stay in these woods during the day, as they afforded the only protection obtainable from machine guns, shrapnel and high explosive. At the time this occurred American gas officers generally understood the necessity of getting troops out of a mustard gas infected area. Accordingly all began searching for places safe from the mustard gas. ”

“ The non-persistent gas may be used at all times where one wants to get rid of it in a few moments—the persistent gas wherever one wants to keep the enemy under gas for days at a time. We will use mustard gas on strong points in the advance, on flanks, on distant areas one will not expect to be reached, and as our own protection of masks and clothing increases toward perfection we will use it on the very fields you expect to cross. ”

“ The distinction lies rather in the magnitude and incidence of use of the chemical appliance on the battle-field, while depending on its novel nature. A new substance, possessing potential strategic value, may be wasted, and its surprise effect lost, in some local affair. This applies to the use of mustard gas by the Germans and to our own use of the Livens projector. Our armies were surprised and our plans modified by the German use of mustard gas at Ypres and Nieuport. ”

“ The importance of protection against mustard gas burns led to extensive researches being made with a view to finding a cloth which would be comfortable and porous and while stopping mustard gas would yet be sufficiently durable and comfortable to be issued to infantry troops as well as to artillery and other special troops. ”

“ We have today at Edgewood Arsenal some 1,400 tons of poisonous gases not including chlorine. Those gases have been manufactured, practically every ounce of them, for three years, and are yet in almost perfect condition. Our chemists believe they can be kept in the future for ten years and perhaps longer. Our gas shells then will have the life almost of a modern battleship, while the cost of a million will be but a fraction of the cost of a battleship. What I have just said applies particularly to liquid gases such as phosgene, chlorpicrin, and mustard gas. ”

“ The speed of the aeroplane will atomize it. In this way, gas can be sprinkled over whole areas that must be crossed in battle. The Lewisite, of which we have heard considerable, will be used. It is less persistent than the mustard gas, but like mustard gas it produces casualties by burning. Unlike mustard gas, however, the burns from a quantity equal to three drops will usually cause death. The material can be made up by hundreds, even thousands, of tons per month. ”

“ The use of sufficient quantities of mustard gas will almost certainly stop the occupation of areas by the enemy and probably even stop his crossing them. It also enables strong points which it is not desired to attack to be completely neutralized,—that is, made so unhabitable that the area must be evacuated. ”

“ This last assertion requires substantiation; for it is at least a grave theoretical error to add a non-inflammable gas to a combustible one, as is seen in the lower efficiency of all flames when burning in common air in comparison with that which they exhibit in oxygen; while from the practical aspect, so harmful is carbon dioxide in an illuminating gas, that coal-gas and carburetted water-gas are frequently most rigorously freed from it, because a certain gain in illuminating power may often thus be achieved more cheaply than by direct enrichment of the gas by addition of hydrocarbons. ”

“ Gaseous carbon, on the other hand, emits more heat than an equivalent quantity of hydrogen, [Footnote: In a blowpipe flame hydrogen can only burn to gaseous, not liquid, water.] even when it is only converted into the monoxide. In other words, a gaseous fuel which consists of hydrogen alone can only yield that temperature as a maximum at which the speed of the dissociation of the water vapour reaches that of the oxidation of the hydrogen; and were carbon dioxide the only oxide of carbon, a similar state of affairs would be ultimately reached in the flame of a carbonaceous gas. ”

“ Those gases which contain less methane contain all the more hydrogen, viz. 2.9 to 29.8%. There is also some ethylene, ethane and carbon monoxide, rarely exceeding 2 or 3%. The quantity of incombustible gases—oxygen, carbon dioxide, nitrogen—ranges from mere traces to about 5%. The density is from 0.45 to 0.55. The heating power of 1000 cub. ft. of natural gas is equal to from 80 to 120 ℔, on the average 100 ℔, of good coal, but it is really worth much more than this proportion would indicate, as it burns completely, without smoke or ashes, and without requiring any manual labour. ”

“ It would certainly be esteemed one of the greatest discoveries of the age if any one could succeed in condensing coal gas into a white, dry, solid, odourless substance, portable, and capable of being placed upon a candlestick, or burned in a lamp. Wax, tallow, and oil, are combustible gases in a solid or fluid form, which offer many advantages for lighting, not possessed by gas: they furnish, in well-constructed lamps, as much light, without requiring the expensive apparatus necessary for the combustion of gas, and they are generally more economical. ”

“ There is no escape of combustible matter unconsumed, which is so great a nuisance [101] in all our common lights. The products of the combustion are water and carbonic acid gas [21] . The accurate and elegant experiments of Dr. W. Henry have shewn in the most satisfactory manner, that considerably less carbonic acid is produced by the flame of coal-gas, than by that of oil, tallow, or wax [22] , which [102] sufficiently refutes the absurd notions that have been circulated respecting the pernicious effects of gas-lights. ”

“ The same occurs when the temperature of any portion of the hydrogen is reduced below that intensity required for the combustion of the newly separated charcoal. Solid bodies, as tallow, oils, and fats, which burn with flame, are converted into the state of gas by the heat required to kindle them, and it is this gaseous matter which suffers combustion, and not the substance which produces it. ”

“ When the carbonic acid is absorbed by lime-water, if the gasses have been properly proportioned, no gazeous residue is left, except accidental impurities. Though carburetted hydrogen gas, is sometimes naturally produced in coal-mines, and occasionally mixes with common air, producing dreadful explosions, yet when coal-gas is mixed with common air, it does not explode unless the gas be to the air as 1 to 10 nearly. Such are the leading chemical habitudes of this gazeous product. The varieties of carburetted hydrogen gas all agree in being inflammable ”