president's ADDRE-^S — SECTION B. 35 



6OQ0 C. and under a pressure of 150 to 200 atmospheres were coii- 

 siderable, but were successfully overccme. In 1917 the factory 

 erected by the Badische Company at Oppau produced 93,000 tons 

 oi pure NH3 by this process, whilst a second factory at Merse- 

 burg, near Halle, has twice that capacity. Besides the Haber 

 process, the Germans were also using the cyananiide process and the 

 Pauling arc process for producing synthetic nitrogen ccmpounds, 

 but of the three the Haber process has proved itself to be the 

 most economical and impoi'tant. Had it not been for these pro- 

 cesses, the Germans would have rapidly run short of nitrogen 

 compounds both for agriculture and for the manufacture of muni- 

 tions, and could hardly have survived one year of war. Perhaps 

 this lesson is not entirelv without interest for Australia. 



In view of their peculiar notioins of honour and humanity, it 

 is not surprising that early in the war the Germans yielded to 

 the temptation to make use of the great superiority in chemical 

 resources, which they then possessed, in an attempt to overwhelm 

 the resistance of the Allies by launching surprise attacks with 

 poison gas. As already mentioned, the end, from their point of 

 view, veiy nearly justified the means; but it may be doubted 

 whether towards the close of the war, when the Allies' reply in 

 kind was becoming effective, they were quite so pleased with their 

 innovation. 



Owing to the ease with which free chlorine can be absorbed 

 and rendered harmless, it was soon sujierseded for offensive pur- 

 poses by various poisonous compounds, most of which, however, 

 contained chlorine as a constituent. Of these ccmpounds perhaps 

 the most important were phosgene and jS^dichlordiethyl sulphide, 

 the so-called " mustard gas," the latter being first used by the 

 Germans in July of 1917. Apparently owing to faulty organiza- 

 tion on the part of the Department originally concerned, the 

 production of podscns in Britain failed for some considerable time 

 to meet requirements; but in April of 1918 the whole of the manu- 

 facture and supi>ly was transferred to the Explosives Department. 

 As this manufacture was given the highest priority, the whole of 

 the comprehensive scientific and technical resources of the latter 

 Department were at once applied to it, and a vigorous programme 

 was taken up. In the meantime a simplified method for making 

 mustard gas by the action of ethylene on sulphur mcnochlcride 

 had been discovered in the Chemical Department of the University 

 of Cambridge; and, although the working out of this method on 

 a technical scale was still far from complete, its advantages over 

 the cumbrous method used by the Gennans were so obvious that 

 it was decided to adopt it. An existing factory which had been 

 shut down was rapidly reconstructed for the new manufacture, 

 first en an experimental and later on a large scale; and, owing 

 to the strenuous and self-sacrificing labours of the technical staff, 



