WWI and Chemistry in Britain and Germany

Last Wednesday, Emeritus Professor Alan Dronsfield FRSC (currently based at the University of Derby), delivered a timely lecture entitled "The First World War - Its Chemical Origins". Alan outlined the complexity of both the causes of the war and the alliances on each side. He described World War I as the war of the chemists, with World War II being the war of the physicists. Both sides in the conflict were confident they would win fairly quickly. Alan suggested that no nation declares war unless it is confident it will win. The Allies believed that, being largely land locked, they would be able to blockade Germany, thereby eliciting their surrender.

In particular it was considered an easy option to block the shipment of Chile saltpetre between Germany and Chile, traditionally a vital ingredient in the manufacture of fertilisers and explosives, cordite in particular. Whilst poison gases are often associated with WWI, Alan said that in terms of deaths, they had a much smaller impact than contemporary developments in shells, bullets and explosives chemistry.

Shells and Bullets Major-General Henry Shrapnel (1761–1842), an English artillery officer, developed an artillery shell that had a timer device that was set to break open the shell at a specified time after being fired, releasing small metal balls in all directions. When fired in a high trajectory by howitzers, and with the shell exploding just above the ground, these proved to be lethal weapons in trench warfare; traditional shells that exploded on impact with the ground were generally less devastating.  The development of cordite facilitated the development of high precision fuses for the first time, which enabled a gun crew to adjust the timing of the fuse according to what happened with the first few shells, with the aim of timing the explosion to coincide with their exploding just above trenches. German forces redesigned the components of the shells to maximise their impact. Due to the development of the ‘all in one’ bullet a rifleman could shoot far quicker than the twice per minute of a good rifleman in previous centuries. The introduction of the machine gun was a means of firing the ‘modern’ bullet at a very high rate.

Chemistry Contrary to the British strategy of blocking German access to the raw materials for the fabrication of explosives, Germany became self-sufficient in vital supplies through its vibrant chemical industry. After Perkins made the first synthetic dye derived from coal tar, a key commercial target was the synthesis of the red dye, Madder - for centuries the Madder shrub that grows in southern Europe had been a source of this deep red dye. At this point in the proceedings, Alan enlisted the help of a keen young member of the audience for a "hands on" demonstration of dying wool and silk. The experiment was a great success, and nobody was hurt during the process!

Progress in the synthesis of dyes wasn’t helped by the limited understanding of chemical notation and a consensus estimate of atomic weights - whilst John Dalton had advanced our understanding in 1803, he also caused confusion, e.g. was water HO or HOH?The Karlsruhe Congress in 1860 was an attempt to bring some order to these issues, but it closed without general agreement. However, ideas proposed by Cannizzaro were picked up by Meyer, a German chemist, and this was instrumental in bringing order and predictability to industrial synthesis in particular.

With alizarin having already been identified as an active ingredient in Madder, the new structural formalism helped German chemists Grabe and Libermann, working for BASF, to find a way, in 1868 to synthesise alizarin from anthracene, and at a fraction of the cost of the natural product. This proved to be a milestone in the international dye industry and triggered a major development of the chemical industry in Germany; at the time few of the best brains in Britain were attracted to chemistry: Academia being too lofty for contemplating the "applied sciences"!

This industrial lead was further advanced when in 1909 Fritz Haber discovered how to manufacture ammonia from the nitrogen in air, thereby providing a means of producing fertiliser, nitric acid and explosives. This process undermined the Allies’ hopes of a blockade of Chile saltpetre, hastening a German surrender.  During WW1 Haber was an enthusiastic advocate of chemical warfare and directed German research seeking improvements in poison gases. For example, he sought chemicals that weren’t absorbed by the filter in gas masks as was the case with chlorine. One approach was to disperse arsenical powders that would pass through a gas mask and cause sickness. Then the gas would get you!In 1918 Haber was awarded the Nobel Prize, a controversial decision because of his work on poison gases during WW1. Although the allies all had active chemical warfare programmes as well. Alan spoke about him being a German patriot who, because he was Jewish, emigrated in 1934 with the build-up of National Socialism in Germany, only to die a few months later in Switzerland after a short sojourn in England.

Alan finished his presentation by dramatically illustrating the nature of WW1 warfare with a series of photographs and slides of poetry written about warfare. This was a very moving finale to a fascinating talk.

Bob Roach and Dave Hornby