Standard Uses for Gas;—Gas Shell.—But gas found an important use besides that of strategic surprise. It became a standard weapon for certain clear and definite tactical purposes. (For some of these, indeed, the factor of local surprise was important.) We refer to the specific use of gas shell for the neutralisation of batteries, roads, and areas, and to the use of cloud gas, prior to offensives for the production of casualties, and wearing down of reserves. The Ypres attack had not by any means established the use of gas for such purposes. There is no doubt that, from this point of view, the experimental period carried on for many months. Naturally, in some respects, there was always an experimental element in the use of gas.
Further German Cloud Attacks.—Two days after the first cloud gas attack the Germans launched a second against the Canadians, with similar results. Quoting from official despatches: "On the early morning of the 24th a violent outburst of gas against nearly the whole front was varied by heavy shell fire, and a most determined attack was delivered against our position east of Ypres. The real attack commenced at 2.45 a.m. A large proportion of the men were asleep, and the attack was too sudden to give them time to put on their respirators." These latter were hurriedly improvised after the first Ypres attack.
Hill 60.—Four more attacks occurred in May, notably in the region of Hill 60. "On May 1st another attempt to recapture Hill 60 was supported by great volumes of asphyxiating gas which caused nearly all the men along a front of about 400 yards to be immediately struck down by its fumes." "A second and more severe gas attack under much more favourable weather conditions enabled the enemy to recapture this position on May 5th. The enemy owes his success in this last attack entirely to the use of asphyxiating gas." "It was only a few days later that the means which have since proved so effective of counteracting these methods of making war were put into practice." (Official despatches, 1915.) The despatch further described how violent bombardments, the confusion and demoralisation from the first great gas surprise, and subsequent almost daily gas attacks, prevented the proper reorganisation of the line in question.
Origin of German Gas Shell.—After May a long period elapsed during which the Germans confined their war chemical activities on the front to the use of gas shell. Schwarte's book describes their origin as follows:—"The main idea which influenced the FIRST construction of a German projectile containing chemicals (October, 1914) was that of adding to the charge an irritant substance, which would be pulverised by the explosion of the projectile, and would overwhelm the enemy with a cloud of dust. This cloud would hover in the air and have such an effect upon the mucous membranes that, for the time being, the enemy would be unable to fight in such an atmosphere. By altering the construction of the 10.5 c.m. universal shell for light field howitzers, the `N.i' projectile was created in the form of 10.5 c.m. shrapnel, the bullets of which were embedded in a sternutatory powder (double salts of dianisidine) well stamped down, instead of an explosive. By means of the propelling charge and the grinding effect of the bullets, this powder was pulverised on explosion. The irritation caused was not very intense, lasted only a short, time and affected only a limited area and therefore it was of no importance in the field, but the initial step had been taken. Liquid irritants soon came to the front—xylyl bromide and xylylene dibromide—a mixture used later under the name of T. stuff, bromo-acetone and brominated methyl ethyl ketone, later introduced under the name of B. stuff and Bn. stuff."
During experiments they gave such improved results in intensity, in power of lasting and of affecting an increased area, that practical results in the field were ensured. The use of these liquids in projectiles, however, was contrary to the accepted idea with regard to artillery, according to which liquid materials should not be used for ballistic reasons. Specially arranged shoots were required to prove that the projectiles in use in the German Army could also be used from the ballistic point of view when filled with liquids.
In this way the first effective German gas projectile, the T. shell for heavy field howitzers, was evolved (January, 1915).
Early German Gas Shell.—The first important use of German gas in shell was that of brominated and chlorinated organic compounds, T. and K. stuffs. Schwarte's book tells us "the use of these projectiles was continually hampered by lack of understanding on the part of the troops which it was difficult to overcome. In the summer of 1915 it was practically in the Argonne alone that any considerable results were attained by the new projectiles." And he describes how the first elements of the new gas tactics were developed there.
A Successful Experiment.—The development of the gas shell, the use of which, generally speaking, is independent of, but co-ordinated with, wind direction, may have received stimulus from the fact that the prevailing wind, so important for cloud gas, favoured the Allies. It is clear that this period was an experimental one, but we know that by August, 1915, German military opinion had crystallised out to the extent of formulating certain rules, issued as Falkenhayn's orders for the employment of gas shell. These early orders defined two types of shell, one persistent, for harassing purposes, and the other non-persistent, to be used immediately before an attack. They specified the number of shell to be used for a given task. But in this they were unsound and it is clear that the Germans had an exaggerated opinion of what could be achieved with a small number of shell. They adhered too closely to high explosive practice. Various documents reveal the fact that the Germans were much more satisfied with their gas tactics than they would have been had they possessed information with regard to our losses from their shell. They attached insufficient importance to the value of surprise and highly concentrated shoots, and had a mistaken idea of the actual specific aggressive value of their early types.
Lachrymators at Loos, 1915.—Germany commenced the manufacture of lachrymators, crude brominated xylene or brominated ketones, early in, or perhaps before 1915. These substances caused great inconvenience through temporary blindness by lachrymation, but were not highly toxic. In June, 1915, however, they began to produce lethal gas for shell. Falkenhayn's orders for the use of gas shell, mentioned above, although they represent by no means the best final practice, were definite evidence that gas had come to stay with the Germans. The writer has vivid recollections of their use of lachrymators in the Loos Battle. Batteries in the open, under the crest near the Lens road, were in position so that the wind direction practically enfiladed them, sweeping along from the direction of Le Rutoire farm. Gas from German shell, borne on the wind, was continually enveloping the line of batteries, but they remained in action. It was on this occasion while watching the bursting gas shells from the outskirts of the mining village of Philosophe that Major-General Wing was killed outright by a high explosive shell. These gas shells certainly did not achieve the results which the Germans expected, although they were not without effect. Demolished villages, the only shelter for troops in a desolate area, have been rendered uninhabitable for days by a concentrated lachrymator enemy shoot of less than one hour. Again, walking into gas "pockets" up a trench one has been stopped as by a fierce blow across the eyes, the lachrymatory effect was so piercing and sudden. The great inconvenience which was occasioned to parties engaged in the routine of trench warfare, on ration or engineering duties, and the effect on movement in the rear after an assault, taken cumulatively, represented a big military factor.
The Flammenwerfer.—There can be no doubt that this period marks increasing German willingness to live up to their "blood and iron" theories of war, and, in July, 1915, another device with a considerable surprise value was used against us: the flame projector, or the German flammenwerfer. Field-Marshal Sir John French signalled the entry of this new weapon as follows: "Since my last despatch a new device has been adopted by the enemy for driving burning liquid into our trenches with a strong jet. Thus supported, an attack was made on the trenches of the Second Army at Hooge, on the Menin Road, early on 30th July. Most of the infantry occupying these trenches were driven back, but their retirement was due far more to the surprise and temporary confusion caused by the burning liquid than to the actual damage inflicted. Gallant endeavours were made by repeated counter-attacks to recapture the lost section of trenches. These, however, proving unsuccessful and costly, a new line of trenches was consolidated a short distance farther back."