In 1915, the radium, which had been safely deposited in Bordeaux, was brought back to Paris, and not having time for regular scientific research, I decided to use it to cure the wounded, without, however, risking the loss of this precious material. I proceeded to place at the disposal of the Health Service not the radium itself, but the emanation which can be obtained from it at regular intervals. The technique of the use of the emanation can readily be employed in the larger radiumtherapy institutes, and, in many ways, is more practicable than the direct use of radium. In France, however, there was no national institute of radiumtherapy, and the emanation was not used in hospitals. I offered to furnish regularly to the Health Service bulbs of radium emanation. The offer was accepted, and the "Emanation Service," started in 1916, was continued until the end of the war and even longer. Having no assistants, I had, for a long time, to prepare these emanation bulbs alone, and their preparation is very delicate. Numbers of wounded and sick, military and civil, were treated by means of these bulbs. During the bombardment of Paris, the Health Board took special measures to protect from shells the laboratory in which the bulbs were prepared. Since the handling of radium is far from being free of danger (several times I have felt a discomfort which I consider a result of this cause), measures were taken to prevent harmful effects of the rays on the persons preparing emanation. While the work in connection with the hospitals remained my major interest, I had many other preoccupations during the war. After the failure of the German offensive in the summer of 1918, at the request of the Italian government, I went to Italy to study the question of her natural resources in radioactive materials. I remained a month and was able to obtain certain results in interesting the public authorities in the importance of this new subject. It was in 1915 that I had to move my laboratory to the new building in the rue Pierre Curie. This was a trying and complicated experience, for which, once more, I had no money nor any help. So it was only between my journeys that I was able, little by little, to do the transportation of my laboratory equipment, in my radiologic cars. Afterwards, I had much work in classifying and distributing my materials, and arranging the new place in general, with the help of my daughter and of my mechanic, who, unfortunately, was often ill.