About this same time, George Sagnac, a young physicist engaged in the study of X-rays, often came to discuss with my husband the analogies one could expect to find between these rays, and their secondary rays, and the radiations of radioactive bodies. They worked together on the investigation of the electric charge carried by the secondary rays. Besides our collaborators we saw very few persons in the laboratory; however, from time to time some physicist or chemist came to see our experiments, or to ask Pierre Curie for advice or information; for his authority in several branches of physics was very well recognized. And then there were discussions before the blackboard,--discussions which are pleasantly remembered to-day, because they stimulated an interest in science and an ardor for work without interrupting any course of reflection, and without troubling that atmosphere of peace and contemplation which is the true atmosphere of the laboratory. [Footnote 7: This last publication was issued in common with G. Bemont, who had collaborated with us in our experiments.] [Footnote 8: I quote, as an example, a letter addressed to Pierre Curie by A. Paulsen, thanking him for radioactive products loaned him in 1899: "Den Damke Nordl's Expedition Akureyi, 16 Oct. 1899. Monsieur, and most honored colleague, "I thank you warmly for your letter of August 1, which I have just received in the north of Iceland. "We have abandoned all the methods hitherto employed to establish in a fixed conductor the potential that exists at certain points in the mass of air that surrounds it, and are using only your radiant powder. "Accept, Monsieur, and most honored colleague, my respectful salutations and my renewed thanks for the great services you have rendered my expedition. "ADAM PAULSEN."] CHAPTER VI THE STRUGGLE FOR MEANS TO WORK. THE BURDEN OF CELEBRITY. THE FIRST ASSISTANCE FROM THE STATE. IT COMES TOO LATE