German gas attack at Bolimów

On the morning of 31 January 1915 German artillery opened fire on the Russian trenches on the Rawka, near Bolimów. Among the ordinary shells, about 18,000 shells filled with a tear agent fell on the Russian positions. It was the first attack of this war in which chemical weapons were used on such a scale. It ended in failure: in the frosty air the gas hardly evaporated.

A new attack on the Rawka

Since mid-December 1914 the front on the Bzura and the Rawka had stood almost still. At the end of January General August von Mackensen’s German Ninth Army was given the task of making a strong attack in this sector. It was no longer only about the road to Warsaw. The command of the Eastern Front, Field Marshal Paul von Hindenburg and General Erich Ludendorff, was preparing a great offensive in East Prussia for the beginning of February. The attack at Bolimów was meant to draw in the Russian reserves and divert attention from Masuria.

On a narrow sector between Humin and Wola Szydłowiecka the Germans concentrated several divisions of General Kurt von Morgen’s I Reserve Corps and of XVII Corps. According to Russian accounts they were supported by about 600 guns, including heavy howitzers and two Austro-Hungarian 305 mm mortars. Facing them stood the divisions of the Russian VI Corps of General Vasily Gurko, part of General Vladimir Smirnov’s Second Army.

“T” shells

Chemical shells were a novelty. The agent they were filled with, xylyl bromide, had been proposed by the chemist Hans Tappen of the Prussian War Ministry, the brother of one of the officers of the German General Staff. After his name the Germans called it T-Stoff, and the shells “T” shells. They were modified 15 cm howitzer shells which, alongside the explosive charge, contained a few kilograms of the liquid agent. After the burst the liquid was supposed to evaporate and form a cloud of gas irritating the eyes and the respiratory tract. The first trials on the proving ground had been carried out only a few weeks earlier.

Tear agents were not meant to kill but to incapacitate the defenders and drive them out of their trenches. Their use raised doubts, because the Hague Convention of 1899 prohibited the use of projectiles whose sole object is the diffusion of asphyxiating or deleterious gases. The Germans argued that their shells also contained an explosive charge and that tear gas was not poisonous.

Frost instead of a cloud

The day was frosty. According to the Polish Wikipedia the temperature was about –3 °C. In such conditions xylyl bromide hardly evaporated, and the liquid froze or soaked into the snow. Accounts of the effects differ. According to many works the Russians did not notice at all that they had been attacked with gas and did not warn their allies. Russian reports, however, mentioned the choking effect of gases from the German shells, and prisoners taken by the Germans complained of watering eyes and headaches. According to some sources the wind also blew some of the gas back towards the German lines.

The infantry attack, launched after a bombardment of several hours, brought the Germans a local success. According to Russian accounts, by late afternoon they had driven units of several Russian divisions out of the first line of trenches and broken into their positions at Humin and Wola Szydłowiecka. There was, however, no breakthrough. That same night the Russians began to bring up reserves and prepare a counter-attack.

The gas attack at Bolimów proved a failure, and its significance was appreciated only later. The failure in the frost led the Germans to look for other ways of using gas. A few months later, in April 1915 at Ypres and in May again at Bolimów, they would use chlorine released from cylinders.