ballistite method was adopted for nitroglycerin powder, and resulted in an economy of material.
Glycerin substitutes were the most difficult to procure. Glycerin made from sugar was inferior to that made from fats. Moreover, sugar also was scarce. But nothing else had quality requirements.
The inferior purity of the materials, already referred to, produced a number of evils. Some of these did not prove any particular draw- back in use. A more serious matter, however, was deficient or un- evenly distributed gelatinization of the wood cellulose. These ir- regularities were shown externally by the presence of little white spots, and resulted in the detonation of the powder on discharge. Only by the most drastic inspection could these mishaps be avoided.
A still greater disadvantage lay in the reluctance of these war powders to ignite, which endangered the lives of the gunners by hang-fires. For this reason, in Austria-Hungary, the use of a black powder-priming, which had been discarded in peace-time, was re- sumed, with certain precautions.
The lesser inflammability caused a quantity of unburned powder to remain in the fore-part of the bore after firing. This was especially the case with the slow-burning tubular powders. In certain guns this occurred in a regular manner ; the same amount was always left un- consumed and the effect on the accuracy of the shooting was thus negligible. But if the amount varied the shooting was ineffective.
But the worst consequence of inferiority in the quality of powder was the increased number of barrel-burstings. For reasons already
fiven this was most frequent in the Austro-Hungarian long guns, n the steel-barrelled field guns the length of the gun's life diminished from 1, 800 shots to 800 an impossible state of things. The ad- vantages of the howitzers and mortars here becomes apparent. The 15-cm. howitzer lasted out 14,000 shots, and the 3O-5-cm. mortar as many as 2,500. The German guns manifested about the same endurance, thanks mainly to the less eroding nature jof the nitro- cellulose powder employed.
To find a remedy became an urgent necessity in Austria-Hungary. As one expedient reduced charges were introduced to be used in lieu of the service-charge when the nature of the fighting permitted; as another, following the German example, recourse was had "to the preparation of a powder poor in nitroglycerin. The limited size of chamber did not permit the use of pure nitrocellulose powder; but finally success was obtained with powders containing only 13% and 25% of nitroglycerin. The life of the guns rose forthwith to 12,000 shots. But the output of powder declined, because a large number of the batches produced did not give the required density of loading. However, the method was advantageous owing to its economy of glycerin, which was so scarce.
In Germany good results were achieved with ammon powder, which, made by the new method, partly took the place of nitro- cellulose powder. It was soon employed for all calibres. This highly hygroscopic powder could be easily made damp-proof in metal cartridge cases. Where as, for instance, in certain of the foot- artillery weapons the powder was made up in bags, the ammon powder was enclosed in a layer of nitroglycerin powder. Ammon powder had the great merit of producing little flame at the muzzle.
The bright flashes of the large calibres, which were so inconvenient at night, by means of anti-flash were reduced by " flash-dampers," i.e. layers of common salt in front of the powder, which covered the light by producing a large volume of smoke. These were added to the cartridges immediately before firing. The manufacture of black powder remained unchanged, and as the output was comparatively small the production was unaffected by the scarcity of raw material.
In Austria-Hungary, especially, all these difficulties, combined with the small output capacity, seriously interfered with extensive mass-production, and moreover, as the powder production nearly always lagged behind that of the other munitions, it was necessary to make use of insufficiently settled and ballistically unstable powder. Moreover, failure to issue the powder charges in batches according to manufacture was the cause of much bad shooting, which the troops erroneously attributed to defects in the guns or the shells.
Gas Shells. -The use of gas in artillery shells, and with special kinds of apparatus, was one of the novelties reserved for the World War. After a semi-experimental stage in the early months of the war the ultimately general and comprehensive employment of gas shell had its beginnings in the cloud method and in the trench-mortar gas shell. It was anything but popular with the German troops, who did not in fact appreciate its value until after long experience.
It was inevitable that the inadequate chemical resources of Austria-Hungary should here play a subordinate part beside the fully matured industry of Germany, whose chemical development had, moreover, been powerfully stimulated by its activities during the war. The Danube monarchy was absolutely dependent on Germany in this respect. For this reason, and also because the enemies mainly confronting the Austro-Hungarians made but small and ineffective use of gas, this form of warfare was less developed on their front, and was not properly appreciated by the troops till nearly the end.
In the early months, to the middle, that is, of 1915, the Austro- Hungarian artillery was provided with lachrymatory shells in very limited numbers. The filling was T-stoff, a preparation of bromine. The troops did not understand their use at all ; they were never fired in large quantities, and very little was achieved by their use.
In Austria-Hungary the issue of gas shells, i.e. of B. and C. shells,
was begun in 1916 and 1917, when the newly constituted special battalion were seen to have obtained no appreciable results with cylinder gas. 1 The B-gas was bromo methylketone or bromacetone, corresponding to the German B-gas. The C-gas was bromo-cyanide. When C-gas was used the shell walls had to be coated with lead. But if the gas may be called efficacious the shells were not so. The chief cause lay in the fact that effect was not to be expected unless large quantities were used, and the available supply did not allow of this. The troops, therefore, thought very little of this means of fighting, and with reason.
The effect of the German gas-shooting in the West, and especially the brilliant results obtained with gas against the enemy artillery and even against high-sited positions by the German batteries in the combined offensive of Caporetto in 1917, spurred on Austria-Hun- gary also to the manufacture of gas shells in large quantities. Not only was the production of the B. and C. shells increased, but phos- phorus shells were also made, and ultimately the gases adopted were those used by the Germans (blue-cross yellow-cross green-cross). As far as the use of these gases was concerned Austria-Hungary was dependent on Germany for her material to the end of the war. Except in the case of the shells previously referred to, the Austro- Hungarian gas shells were always filled in Germany, as the home establishments were not completed. Hence only Germany's proce- dure need be considered here. The following information is taken from Lt.-Gen. Schwartz's Technik im Weltkriege.
The first German shell with chemically active gas appeared in October 1914, and was the Ni-geschoss of the lo-5-cm. field howitzer; the filling consisted of double salts of dianisidin firmly pressed in between the bullets, and acted as an irritant when pulverized. The effect was inconsiderable, being limited in range and of short dura- tion. In Jan. 1915 much more effective gases such as xylylbromide (T-gas) and mono- and di-bromethylmethylketones (B-gas) were used at first in the 15-cm. howitzer shells, afterwards for trench mortars. With these only local effects of limited scope could be obtained. The necessary mass-effect could not be attained because of the limited number of howitzers and trench mortars, but chiefly because the best method of working had not yet been discovered.
For the T-gas shells, which couldnot be used in very cold weather, were substituted the T- and B-gas in the " T-green " shells, partly because the mixture answered better. In the summer of 1915 began the use of K-gas chlormethyl-chloroformate which differed from the T-gas in its lower persistency and its greater irritant action on the organs of breathing. This indicates the reason of their respective uses in defence (T-gas) and attack (K-gas).
These shells, which were intended to have splinter effect as well, contained a l-5-kgm. charge of trotyl. It was a drawback in the manufacture that in order to protect the shell-wall the gas had to be enclosed in leaden flasks secured in paraffin or magnesium cement. Later on porcelain was used. They contained 2 kgm. of the gas.
There followed the period of cylinder gas and of projectors which were first used by the British. Even on the western front the cloud- gas did not fulfil expectations; the gas-bombs of trench mortars, however, were used with satisfactory results throughout the war.
During the summer of 1916 the green-cross ammunition was introduced. In that year the German artillery, following the example of the French, at last turned to the manufacture of gas shells filled purely with gas. H.E. -effect being abandoned, mass- effects with gas then became possible.
The experiments made led to the adoption of green-cross shells for all calibres. Per-stoff (di-phosgene) was used for the filling, which was as poisonous as the phosgene used by the French, but was unaffected by iron and also stable on explosion. The manufacture and filling were both simple. From May 1916 until the end of the war green-cross ammunition was in use as offensive material. It permitted of large-scale gas effect without being dependent on the direction of the wind as was cylinder gas.
At first the French mask was ineffectual against it. But they soon contrived an efficient gas-mask, and Germany was obliged to bring forward other gases. These were yellow-cross and blue-cross. Yellow-cross, i.e. Sym. dichlordiethylsulphide, which had no actual- ly poisonous properties, was a high-persistency gas and was used to " infect " the terrain for days on end. It was almost odourless and was proof against the action of iron and water. This was the famous " mustard gas." Strict precautions had to be observed in the man- ufacture of this gas, which was used in all calibres.
The combination of H.E. action with the yellow-cross gas action came to be desired for purposes of surprise. This brought into exist- ence the yellow-fross H.E. shell, in which the chemical and the explosive charge were separated by a diaphragm.
Yellow-cross was at first used in combination with blue-cross in the defensive battle in Flanders in July 1917, and produced a great effect. The latter (blue-cross, diphenylchloroarsine) was an irritant which proved effective in penetrating gas-masks, the German one included. The effect was to force the enemy to take off his mask, and
1 A gas attack, made from the region of St. Michele, near Gorizia, in the summer of 1915, had indeed (as was averred by the prisoners taken) a very great effect ; the Italians lost a thousand either killed or overcome by the gas ; the circumstances, however, prevented any extensive tactical results.
