One of my first cares was to have trees planted in the limited grounds of my laboratory. I feel it very necessary for the eyes to have the comfort of fresh leaves in spring and summer time. So I tried to make things pleasant for those who were to work in the new building. We planted a few lime trees and plane trees, as many as there was room for, and did not forget flowerbeds and roses. I well remember the first day of bombardment of Paris with the big German gun; we had gone, in the early morning, to the flower-market, and spent all that day busy with our plantation, while a few shells fell in the vicinity. In spite of the great difficulties, the new laboratory was organized little by little, and I had the satisfaction of having it quite ready for the beginning of the school-year 1919-20, the period of demobilization. In the spring of 1919, I organized special courses for some American soldier students, who also studied with much zeal the practical exercises directed by my daughter. [Illustration: _Photo by U. S. Signal Corps._ Mme. Curie instructing American soldiers in her Paris laboratory.] The entire period of the war was for me, as for many others, a period of great fatigue. I took almost no vacation, except for a few days, now and then, when I went to see my daughters on their holidays. My older daughter would scarcely take any, and I was obliged to send her away sometimes to preserve her health. She was continuing her studies in the Sorbonne, and besides, as said before, was helping me with my war work, while the younger daughter was still in the preparatory college. Neither of them wished to leave Paris during the bombardment. After more than four years of a war which caused ravages without precedent, the armistice came at last, in the autumn of 1918, followed by laborious efforts to reëstablish peace, which is not yet general nor complete. It was a great relief to France to see the end of that dark period of cruel losses. But the griefs are too recent and life still too hard for calm and happiness yet to be restored.