MARIE SKLODOWSKA-CURIE (1867-1934) – A PERSON and SCIENTIST

R. MIERZECKI

MarieR.Mierzecki Sklodowska-Curi Polish ul. Freta 16, 00-227 , e-mail: [email protected].

Marie Sklodowska was born in Warsaw on 7-th November 1867. Her mother was a superior of a well known Polish girl’s boarding- school in the building Freta 16. These schoolrooms are to-day the seat of the Marie Sklodowska-Curie Museum and of the Polish Chemical Society. The family had a flat in no more existing outbuilding of this building. At that time the name of Poland did not exist on political maps of Europe. Poland was divided between Russia, Prussia and Austria. Warsaw was the capital of the Russian sector called 1815-1864 the Polish Kingdom, but after the second Anti- russian insurrection in 1863 it was renamed to the Vistula Region. The tsarist authorities intensified the Antipolish and Russifying politics. In the only officially recognised Russian schools Polish was strictly forbidden even for the Polish students; private Polish schools severely supervised by the Russian school authorities gave no official laws. In 1869 the Warsaw Polish University was replaced by the Russian Imperial University. In such conditions the activity of the social class called "inteligencia" played an important role in the Polish population. This class was formed mostly of the nobles, who lost their fortunes as a result of tsarist repression, of some aristocrats, industrialists and representatives of learned professions. Their philosophy was a mixture of romanticism and positivism. Their principal aim was to develop the economic and cultural position of the Polish population having often no regard to the personal benefit. Maria Sklodowska was brought up in such tone. Her mother, born Boguska, as it has already been said, was a teacher. Her grand father J´ozef Sklodowski was a teacher and headmaster of a Polish secondary school in Lublin. Her father Wladyslaw was teaching physics and mathematics in a Russian state grammar-school. Maria was an extremely capable child, the youngest of four siblings. In the age of four she could read. She learned very quickly and had a very good memory. She knew to organise her duties and her time. She was aware of her ability. At the age of eight she lost her oldest sister and at the age of eleven her mother. Maria completed her primary education in a Polish private school and the secondary in a Russian school with a gold medal, when she was fifteen. She became so exhausted, that one year she had to spend on recreation. She smarted from the humiliation that hurtled Polish population from the tsarist authorities. In her future she will have many reasons to be humiliated. At first as a woman she could enter neither the Russian University in Warsaw, as his brother did, nor one of a Polish Universities in Lw´ow or in Cracow, as they accepted only men. Being aware of her ability she decided to study, but studying in Switzerland or in Paris was too expensive for her family. She conceived a plan. She decided to work as a governess for some years and save the wages for future studies. Three years she spent at a landlords’ family in the country. She had then time enough to enlarge her own knowledge and also to teach

Czech. J. Phys. 49/S1 (1999) 29 R. Mierzecki peasant children to read and write in Polish. It was one of the duties of "inteligencia", but persecuted by Russian authorities. There she fell in love with the son of the family, a student of mathematics. A marriage with a governess was an inadmissible misal- liance for the family. They were constrained to resign their plans; the young man was the professor at Warsaw Technical University in free Poland. When her older sister Bronislawa was going to Paris to study medicine Maria started to work at a Warsaw family and with a part of her earning she enabled the study of her sister. Maria was aware that she had to increase her knowledge for studying at Sorbone. In Warsaw some lectures were given at a clandestine Polish university – having no stable place it was called "the flying university". Maria attended these lectures and learned practical methods of chemical analysis in the laboratory of the Museum of Industry and Agriculture. The laboratory organised by her cousin J´ozef Jerzy Boguski former assistant of Dimitrii Mendeleev, was lead by a Warsaw pharmacist Napoleon Millicer. Bronislawa was graduated in medicine in 1891, and in November this year Maria at the age twenty four began at Sorbone her dreamed and planned study in mathema- tics and physics. She reached her aim, which she endeavoured unswervingly. This consistency will be seen in most of her future activities. Maria’s hard discipline of learning and hard life conditions became a legend. Her brother-in-law, Kazimierz Dluski with prevalence had to bring Maria weakened by hunger to her sister. Maria has considered the meal preparation as a lost of time and had not enough money to go to luncheon bars. In 1893 Maria, a woman and a foreigner, came first (between 1825 students) at graduation as licenc´ee es sciences physiques. In may 1894 she was the second of all graduated as licenc´ee es sciences math´ematiques. One of her professors Gabriel Lippmann , who noticed her as a very good student, proposed her a research grant of the Soci´et´e pour l’Encouragement de l’Industrie Nationale for studying the magnetic properties of different metals. Maria had, however, no place to carry on this study. Just at that moment J´ozef Wierusz Kowalski, a professor of physics at the Swiss Fribourg University whose young wife got to know Maria in Poland, visited Paris. Kowalski was acquaintance of a French physicist Pierre Curie, who was ending his doctor thesis on the magnetic properties of substances at different temperature. Pierre was fascinated with Maria’s personality. Maria spent her summer holiday 1894 in Tatra Mountains where her sister and brother-in-law were building a tuberculosis sanatorium. As a graduated from Sorbona she tried also to get a post at the Polish University in Cracow. However, no women were accepted at this university. With tears in eyes she left this town. By the letters Pierre Curie persuaded her to return to Paris to continue her study and to marry him. It was not easy for Maria to decide to work in France and not for the Polish population, but she realised that in Poland she would have very limited possibilities and with her mental powers she would achieve much better results in Paris. In 1895 Marie and Pierre got married. Pierre’s father was a physician and the rank of his family resem- bled that of her own. Returning to Paris Maria decided to prepare a doctor thesis and to stand the test that would enable her to teach in secondary girl-schools. She passed this examination in 1896 and she was the first among other students.

30 Czech. J. Phys. 49/S1 (1999) Marie Sklodowska-Curi

In 1896 Henry Becquerel discovered that uranium compounds themselves emit some rays blackening the photographic plate and ionising the air. This was an unexpected effect and some external conditions enabled its discovery. Becquerel’s observation was only qualitative. decided to study this effect for her doctor theses. The ionisation of the air could be evaluated quantitatively on the base of its electrical conductivity measured with a very sensitive potentiometer. Such a poten- tiometer, a piezoelectric potentiometer had been constructed some years ago by Pierre Curie and Marie used it in her study. First she observed that the ionising power of uranium compounds was dependent on the quantity of the uranium element in the sample. Studying different elements and compounds she found, however, the ionising power of the pitchblende being much greater that the uranium contents should explain it. This was an unexpected phenomenon, but this observation was a result of planned systematic examination of different substances and not an outcome of external events. Marie concluded that pitchblende had to contain an unknown element which radiated the Becquerel’s ray more intensively than uranium itself. With analytical methods learned in Warsaw laboratory she was able to separate step by step fractions from the pitchblende with constantly greater ionising activity. At last she gained a fraction containing mainly bismuth, but its ionising activity was 400 times greater than that of elementary uranium. These results seemed to be so interesting that Pierre decided to leave his own studies and join his efforts with those of his wife. They concluded that in this fraction the unknown element had to be present. They called the new element "polonium" in honour of Maria’s native land and in July 1898 they presented their discovery to the Academie des Sciences in Paris. It was a courageous decision, as they knew no physical or chemical properties of this element and it was only several years later that polonium appeared in the tables of elements. Maria made many efforts to receive pure polonium but all she succeeded was in 1910 the separation of a 2 mg samples that contained 0.1 mg of pure polonium salt. But during these studies already in autumn 1898 Marie and Pierre Curie with the help of Gustav B´emont found in a fraction containing barium an other new element that also ionised the air and in its spectrum a line λ = 3824 was found. In December 1898 the discovery of the element ‘radium’ was announced in the Academy. Hard work to extraction of radium from several tons of J´achymov pitchblende was started. Most of physical work was done with Marie’s hands. Only in 1910 she succeeded to get a pure salt of this element. Although Marie and Pierre Curie realised that their discovery could have a practi- cal application they decided not to patent it and to offer it to the mankind. They were aware of its meaning and hoped to get a position of e.g. university professors that would enable them to continue and develop their investigation. Already in 1898 Pierre received the Gegner award; Marie who initiated the investigation and put much work in its realisation was considered as an assistant of her husband. In 1903 also the Nobel price had to be awarded to Pierre only, and it was Pierre who screened Marie from such humiliation. They did not like to grant interviews, as they were of unswervingly opinion that in science one should be interested in facts, not in persons. They denied, thus, to accept pure honorary distinctions. Only in very exceptional cases the Curies and Marie after the death of her husband agreed to be signatories of social or political actions. Only in 1922 she accepted the membership of the Commission of Intellectual Co-operation by the League of Nations.

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Marie Curie was the first woman who was appointed a lecturer at a French girl- school and, after the death of Pierre, a lecturer and professor at a French university. Several foreign academies and institutions honoured her with their membership, nevertheless her candidature for a membership in the French Academy of Sciences failed with one vote, as she was a woman and foreigner, and she was very humiliated by this fact. All the time Marie Curie worked unswervingly to separate pure radium sample. The positive result of this effort was honoured by the second Nobel price. At the same time in France a great journalist campaign against her was increasing. It was con- nected with her personal relation to the old friend of Pierre and their collaborator from 1898, Paul Langevin. His marriage was not successful, although he and his wife had four children. Marie Curie and Paul Langevin became nearer and nearer friends and his wife let publish Marie’s stolen letters. Marie was the accused as a foreigner who wanted to break up a French family. She was then advised, even by Svante Arrhenius, to postpone the acceptance of her second Nobel price till the affair would not be cleared. She answered this proposition: "The price has been awarded for the discovery of polonium and radium. I think, my scientific work is irrelevant to my personal life." This humiliation made, however, for a year worse her ill health. At that time she was occupied with the construction of a new institute that would be named Institute Curie. The outbreak of the war in 1914 interrupted Marie’s scientific studies. She wanted to help her adopted fatherland in the most effective way. She organised the field Roentgen laboratories that on cars could approach to battle fields to bring help the wounded solders. These cars, where her elder daughter Irene as an assistant, were named "les petits Curies". The war ended, she directed the investigation in the Curie Institute, where many foreign scientists learned radioactivity methods. Between them were Poles and Czechs. From Paris she supervised the works in the Warsaw Laboratory on Radioac- tivity and the construction of the Warsaw Radium Institute. Her two spectacular visits in the United State brought salts containing 1 gram of radium for the Paris Institute and the other for the Warsaw Institute. She was always true to her youth ideas, which she had brought from her Warsaw home. Marie Curie died on 4th July 1934 as a victim of radioactivity, discovered and named by her. On a small cemetery in Scaux on a the gravestone of the family Curie below the inscription ‘Pierre Curie 1859-1906’ a new inscription appeared ‘Marie Curie-Sklodowska 1867-1934’. Marie wanted to be buried together with her husband. In 1995 France honoured this uncommon woman and displaced the coffins of Marie and Pierre Curie to Pantheon. Marie Curie is the first woman honoured in Pantheon for her own merits.

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Fig. 1. The birthhome of Marie Sklodowska-Curie, Warsaw, Freta St. 16, at the end of XIX c. To-day the seat of the Polish Chemical Society and of the Maria Sklodowska-Curie Museum.

Fig. 2. Wladyslaw Sklodowski, father Fig. 3. Bronislawa Sklodowska, mother of Marie Sklodowska-Curie of Marie Sklodowska-Curie

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Fig. 4. Mother and father of Marie Sklodowska in the classroom with their pupils

Fig. 5. Miss Marie Sklodowska at the age of 15. Fig. 6. Miss Marie Sklodowska with her brother J´ozef Sklodowski (first on the right), her sister Bronislawa Sklodowska-Dluska and her brother- in-law Kazimierz Dluski in Tatra Mountain in 1894.

34 Czech. J. Phys. 49/S1 (1999) CONTRIBUTION OF THE INDUSTRIAL CHEMICAL PROCESSING OF PITCHBLENDE IN JACHYMOV´ TO THE FIRST ISOLATION OF RADIUM

M. VOBECKY´ Academy of Sciences of the Czech Republic, Institute of Analytical Chemistry, V´ıdeˇnsk´a 1083, CZ-142 20 Prague 4, Czech Republic

TheContributionM.Vobeck y ´ of pitchblende processing to isolationuranium of radium ore chemical processing plant in J´achymov (St. Joachimstal) started the industrial production of uranium yellow (sodium diuranate) in 1853. This technology was developed by a talented metallurgical Adolf Patera. The insoluble residue from uranium leaching was enriched by radium 226Ra. During more than forty years before discovery of radioactivity, a worthless waste was accumulated in this uranium plant. This waste as radium preconcentrate was present in a suitable chemical form for the subsequent separation of radium. The occurence of this material significantly facilitated the separation and isolation of the first pure weighable amount of radium, necessary to prove the existence of a new chemical element, discovered in 1898 by M. and P. Curie and G. B´emont.

The present paper deals with the introduction of industrial chemical processing of pitchblende in J´achymov in the middle of the last century. The history of technology, developed here by talented Austrian metallurgical chemist Adolf Patera, and some important details of this procedure are not known well so far. Before the discovery of radioactive elements, the waste from uranium pigments production accumulated here in J´achymov, was subsequently changed from worthless substance into a unique intermediate (preconcentrate) for radium preparation. For the radioactive element separated with barium fraction from pitchblende by Curies and a chemist Gustave B´emont [1], the name of radium was suggested by these pioneers of radiochemistry. An indispensable part of the proof of existence of a new element was the finding of its basic properties which determine its position in the periodic system of chemical elements as atomic weight, physico-chemical and spectros- copic properties. At that time, the aim for Curies was obtaining essential amounts of the searched chemical individuum. Uranium minerals of sufficient geological age, on condition that uranium is in a radioactive equilibrium with its daughter products, contain one gram of radium 226 Ra in almost three tons of uranium element or in 3.5 tons of pitchblende (U3O8). From these values it follows that for the preparation of only one hundred miligram of radium it is necessary to process, in the dependence on the uranium content, roughly one ton of the raw material. Into the processed raw material, different minerals and rocks accompanying pitchblende introduce many elements e.g. calcium, iron, arsenic, sulphur, lead, bismuth, copper, vanadium, barium, rare earths etc. The general scheme for radium preperation from pitchblende consists of following multistage operations [2, 3, 4] (1) uranium ore mining, crushing and grinding (2) roasting of raw material to expell most of sulphur and arsenic (3) roasting with soda and salpeter (oxidation of a part of tetravalent uranium to hexavalent form)

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