The Making of the Atomic Bomb: 25th Anniversary Edition

by Richard Rhodes

The most horrible gas of the war, the gas that started a previously complacent United States developing a chemical-warfare capacity of its own, was dichlorethyl sulfide, known for its horseradish- or mustard-like smell as mustard gas.349 The Germans first used it on the night of July 17, 1917, in an artillery bombardment against the British at Ypres. The attack came as a complete surprise and caused thousands of casualties. Defense in the form of effective masks and efficient gas discipline had caught up with offense by the summer of 1917; Germany introduced mustard gas to break the deadlock, just as it had introduced chlorine before. Shells marked with yellow crosses rained down on the men at Ypres. At first they experienced not much more than sneezing and many put away their masks. Then they began vomiting. Their skin reddened and began to blister. Their eyelids inflamed and swelled shut. They had to be led away blinded to aid stations, more than fourteen thousand of them over the next three weeks. Though the gas smelled like mustard in dense concentrations, in low concentrations, still extremely toxic, it was hardly noticeable. It persisted for days and even weeks in the field. A gas mask alone was no longer sufficient protection. Mustard dissolved rubber and leather; it soaked through multiple layers of cloth. One man might bring enough back to a dugout on the sole of his boot to blind temporarily an entire nest of his mates. Its odor could also be disguised with other...