Even though Parliament had voted the creation of a new chair, it did not go so far as to consider the simultaneous founding of a laboratory which was, nevertheless, necessary to the development of the new science of radioactivity. Pierre Curie therefore kept the little workroom at the P.C.N., and secured as a temporary solution of his difficulty the use of a large room, then not being used by the P.C.N. He arranged, too, to have a little building consisting of two rooms and a study set up in the court.
One cannot help feeling sorrow in realizing that this was a last concession, and that actually one of the first French scientists never had an adequate laboratory to work in, and this even though his genius had revealed itself as early as his twentieth year. Without doubt if he had lived longer, he would have had the benefit of satisfactory conditions for his work, but he was still deprived of them at his death at the premature age of forty-eight. Can we fully imagine the regret of an enthusiastic and disinterested worker in a great work, who is retarded in the realization of his dream by the constant lack of means? And can we think without a feeling of profound grief of the waste—the one irreparable one—of the nation's greatest asset: the genius, the powers, and the courage of its best children?
Pierre Curie had always in mind his urgent need for a good laboratory. When, because of his great reputation, his chiefs felt obliged to try to induce him, in 1903, to accept the decoration of the Légion d'Honneur, he declined that distinction, remaining true to the opinion already referred to in a preceding chapter. And the letter he wrote on this occasion was inspired by the same feeling as that in the one previously quoted, when he wrote to his director to refuse the palmes académiques. I quote an extract:
"I pray you to thank the Minister, and to inform him that I do not in the least feel the need of a decoration, but that I do feel the greatest need for a laboratory."
After he was named professor at the Sorbonne, Pierre Curie had to prepare a new course. The position had been given a very personal character and a very general scope. He was left great freedom in the choice of the matter he would present. Taking advantage of this freedom he returned to a subject that was dear to him, and devoted part of his lectures to the laws of symmetry, the study of fields of vectors and tensors, and to the application of these ideas to the physics of crystals. He intended to carry these lessons further, and to work out a course that would completely cover the physics of crystallized matter which would have been especially useful because this subject was so little known in France. His other lessons dealt with radioactivity, set forth the discoveries made in this new domain, and the revolution they had caused in science.
Even though he was very much absorbed in the preparation of his course, and often ill, my husband continued, nevertheless, to work in the laboratory, which was becoming better and better organized. He had a little more space now, and could receive a few students. In collaboration with A. Laborde, he carried on investigations in mineral waters and gases discharged from springs. This was the last work he published.
His intellectual faculties were at this time at their height. One could but admire the surety and rigor of his reasoning on the theories of physics, his clear comprehension of fundamental principles, and a certain profound sense of phenomena which he had by instinct, but which he perfected during the course of a life entirely consecrated to research and reflection. His skill in experiment, remarkable from the beginning, was increased by practice. He experienced the pleasure of an artist when he succeeded with a delicate installation. He enjoyed, too, devising and constructing new apparatus, and I used jokingly to tell him that he would not be happy unless he made at least an attempt of this kind once every six months. His natural curiosity and vivid imagination pushed him to undertakings in very varied directions; he could change the object of his research with surprising ease.
He was scrupulously careful of scientific probity and of complete accuracy in his publications. These are very perfect in form, and none the less so in those parts where he applies the critical spirit to himself, expressing his determination never to affirm anything that does not seem entirely clear. He expresses his thought on this point in the following words:
"In the study of unknown phenomena, one can make very general hypotheses and then advance step by step with the help of experience. This method of progress is sure but necessarily slow. One can, on the contrary, make daring hypotheses in which he specifies the mechanism of phenomena. Such a method of procedure has the advantage of suggesting certain experiments, and, above all, of facilitating reasoning by rendering it less abstract through the employment of an image. But on the other hand, one cannot hope thus to conceive a complex theory in accord with experiment. The precise hypothesis almost certainly includes a portion of error along with a portion of truth. And this last portion, if it exists, forms only a part of a more general proposition to which it will be necessary in the end to return."
Moreover, even though he never hesitated to make hypotheses, he never permitted their premature publication. He could never accustom himself to a system of work which involved hasty publications, and was always happier in a domain in which but a few investigators were quietly working. The considerable vogue of radioactivity made him wish to abandon this field of research for a time, and to return to his interrupted studies of the physics of crystals. He dreamed also of making an examination of diverse theoretical questions.