One never notices what has been done; one can only see what remains to be done.
The first experiments on the biological properties of radium were successfully made in France, with samples from our laboratory, while my husband was living.
Sometimes I had to spend a whole day mixing a boiling mass with a heavy iron rod nearly as large as myself. I would be broken with fatigue at the day's end. Other days, on the contrary, the work would be a most minute and delicate fractional crystallization, in the effort to concentrate the radium.
Unknown in Paris, I was lost in the great city, but the feeling of living there alone, taking care of myself without any aid, did not at all depress me. If sometimes I felt lonesome, my usual state of mind was one of calm and great moral satisfaction.
In 1906, just as we were definitely giving up the old shed laboratory where we had been so happy, there came the dreadful catastrophe which took my husband away from me and left me alone to bring up our children and, at the same time, to continue our work of research.
In chemical terms, radium differs little from barium; the salts of these two elements are isomorphic, while those of radium are usually less soluble than the barium salts.
I was only fifteen when I finished my high-school studies, always having held first rank in my class. The fatigue of growth and study compelled me to take almost a year's rest in the country. I then returned to my father in Warsaw, hoping to teach in the free schools.
During the course of my research, I had had occasion to examine not only simple compounds, salts and oxides, but also a great number of minerals.
A scientist in his laboratory is not a mere technician: he is also a child confronting natural phenomena that impress him as though they were fairy tales.
Pierre Curie came to see me and showed a simple and sincere sympathy with my student life. Soon he caught the habit of speaking to me of his dream of an existence consecrated entirely to scientific research, and he asked me to share that life.
Be less curious about people and more curious about ideas.
I am one of those who think like Nobel, that humanity will draw more good than evil from new discoveries.
There are sadistic scientists who hurry to hunt down errors instead of establishing the truth.
I have frequently been questioned, especially by women, of how I could reconcile family life with a scientific career. Well, it has not been easy.
When radium was discovered, no one knew that it would prove useful in hospitals. The work was one of pure science. And this is a proof that scientific work must not be considered from the point of view of the direct usefulness of it.
I was taught that the way of progress was neither swift nor easy.