When war broke out in 1914, Maria Skłodowska Curie's first act was to carry France's entire radium supply 600 kilometres by train to Bordeaux in a safe-deposit box, and her second was to return to Paris and reinvent herself as a field radiographer. Surgeons at the front were digging for bullets and shrapnel by probing, with the resulting infections and amputations, because every X-ray machine in France sat in a city hospital.
Curie commandeered idle equipment from laboratories and from doctors who had gone to war, and mounted it in vehicles with a dynamo driven off the car's own engine so the units could work where there was no electricity. The soldiers called them petites Curies. By October 1914 the first were operating; eventually about twenty mobile units and two hundred fixed radiological posts were in service, and an estimated one to 1.2 million wounded were examined through them. She did not run this from Paris. She learned to drive, change tyres and clean carburettors, and took a unit to the front herself, accompanied by her seventeen-year-old daughter Irène as assistant.
At the Radium Institute she and Irène trained about 150 women, many with no scientific background, in electricity, anatomy, and plate development. She had earlier refused to patent the radium isolation process, on the grounds that it belonged to science, and she spent her second Nobel money on war bonds. At the end of the war the French government gave Irène a medal and gave Marie no official recognition at all.