Curie, Marie (Maria Sklodowska)

(b. Warsaw, Poland, 7 November 1867; d. Sancellemoz, France, 4 July 1934)

physics.

Maria’s parents, descendants of Catholic landowners, were intellectuals held in poor esteem by the Russian authorities. Her father, Wladyslaw, a former student at the University of Saint Petersburg (now Leningrad), taught mathematics and physics in a government secondary school in Warsaw. Her mother, the former Bronislawa Boguska, managed a private boarding school for girls on Freta Street¹ when Maria, her fifth child, was born. The mother subsequently contracted tuberculosis and gave up all professional activity. Misfortune struck the family again in 1876, when Sophia, the eldest child, died of typhus; in 1878 the mother died.

Denied lucrative teaching posts for political reasons, Professor Sklodowski decided, after moving several times, to take in boarders at his home on Leschno Street, Maria, known familiarly as Manya, gave up her room and slept in the living room; she worked there late at night and put everything in order before the boarders had their breakfast. A gold medal for excellence crowned her brilliant high school studies—in Russian—but her health was weakened (1883). A year in the country with her uncle Sklodowski, a notary in Skalbmierz, near the Galician border, restored her. During this period she formed her profound attachment to nature and to country people.

Upon her return Maria gave lessons to earn money. She was a passionate adherent of clandestine movements supporting Polish political positivism and participated in the activities of an underground university—progressive and anticlerical—whose journal, Prauda, preached the cult of science. Maria read everything in the original: Dostoevsky and Karl Marx, the French, German, and Polish poets; sometimes she even tried her hand at poetry.

In order that her sister Bronia might study in Paris—for France was the land of liberty of which they both dreamed—Maria became a governess (1 January 1886) in the home of M. Zorawski, administrator of the rich estate of the princes Czartoryski (in Szezuki, near Pzasnysz, Plock district, about sixty miles north of Warsaw).

Moved by the poverty and ignorance of the peasant children, Maria gave them lessons after the seven hours devoted to the education of two of her employer’s daughters; she also read many of the books in his scientific library. During the summer Casimir, the Zorawski’s eldest son, a mathematics student at the University of Warsaw, fell in love with her. His family firmly opposed the marriage, however, because Maria was a governess. Although disillusioned, Maria remained with the Zorawskis until the end of her contract (Easter 1889), nearly three years more. Back in Warsaw she again became a governess, dividing her leisure time between her family, the “flying” university, and chemistry. Her cousin Boguski, a former assistant to Mendeleev and director of. the modest laboratory of the Museum of Industry and Commerce, entrusted her to Napoleon Milcer, who had studied under Bunsen.

Meanwhile, Bronia, now a medical doctor, had married Casimir Dluski, also a doctor. They insisted that Maria come to Paris and stay with them. She hesitated, then left with her meager savings (1891). She crossed Germany by train, traveling fourth class, seated on a camp stool. Although her relatives (who lived on the Right Bank) welcomed her warmly, Maria, in order to work as she pleased, preferred to live alone in a modest room ² and content herself with scanty meals. She received an Alexandrovitch Scholarship, which she fully repaid. She passed the licence in physics—on 28 July 1893, ranking first, with high honors—and the licence in mathematics—on 28 July 1894, with honors, ranking second. Her professors, Paul Appell and Edmond Bouty, took notice of her gifts and her enthusiasm; and Gabriel Lippmann opened his laboratory to her.

Maria met Pierre Curie in April 1894 at the home of a Polish physicist named Kowalski. A lively sympathy brought them together and then a deep affection developed. Pierre proposed to her, but before committing herself, she went to Poland to spend the summer near her friends and family. Their correspondence during the summer was conclusive; Maria returned in October having decided to marry Pierre.

Bronia gave her a room at 39 rue de Châteaudun. There she completed the memoir on her first experimental work, “Sur les proproétés magnétiques des aciers trempés,” which Le Chatelier had asked her to write for the Société pour I’Encouragement de I’In dustrie Nationale; Pierre advised her on it. She attended Pierre’s thesis presentation in March 1895, and on 26 July they were married. On 12 September 1897 their daughter Irène was born in their modest apartment, 24 rue de la Glacière.³ A little later they moved to 108 boulevard Kellermann, a building since destroyed. ⁴

Meanwhile, Marie had placed first on the women’s agrégation in physics (15 August 1896). She was looking for a thesis topic while visiting Pierre’s laboratory at the École de Physique et Chimie and occasionally working with him; the director, Paul Schützenberger, welcomed her warmly.

She already shared in the intense excitement of the scientific world: Roentgen had just discovered invisible rays capable of traversing opaque bodies of varying thicknesses, of exposing photographic plates, and of making the air more conductive. Were they really rays? A respected scientist, Henri Poincaré, had advanced in January 1896 the hypothesis of an emission, called “hyperfluorescence,” from the glass wall of a Crookes tube struck by cathode rays. Meanwhile Henri Becquerel, at the Muséum d’Histoire Naturelle, discovered that uranium salts shielded from light for several months spontaneously emit rays related in their effects to Roentgen rays (X rays).⁵ Mme. Curie became enthusiastic about this subject filled with the unknown and, as she later acknowledged, involving no bibliographic research.

The first step in the research was to determine whether there existed other elements capable, like uranium, of emitting radiation. Abandoning the idea of hyperfluorescence, couldn’t one calculate by electrical measurement the effects on the conductivity of air that were revealed by the gold-leaf electroscope? Pierre Curie and his brother Jacques had constructed an extremely sensitive apparatus to measure weak currents; Mme. Curie employed it in testing both pure substances and various ores. In her first “Note” in the Comptes rendus…de l Académie des sciences (12 April 1898) she described the method that she followed throughout her life, the method that enabled her to make comparisons through time and crosschecks with other techniques:

I employed… a plate condenser, one of the plates being covered with a uniform layer of uranium or of another finely pulverized substance [(diameter of the plates, eight centimeters; distance between them, three centimeters). A potential difference of 100 volts was established between the plates.]. The current that traversed the condenser was measured in absolute value by means of an electrometer and a piezoelectric quartz.

In general she preferred the zero method, in which the operator compensates for the current created by the active material by manipulating the quartz. All of her students followed this procedure.

The first results came in 1898: the measurements varied between 83 × 10^-12 amperes for pitch blende to less than 0.3 × 10^-12 for almost inactive salts, passing through 53 × 10^-12 for thorium oxide and for chalcolite (double phosphate of uranium and copper). Thorium would thus be “radioactive” (the term is Mme. Curie’s; its radioactive properties were discovered at the same time, independently, by Schmidt in Germany. The same “Note” contained a fundamental observation: “Two uranium ores…are much more active than uranium itself. This fact…leads one to believe that these ores may contain an element much more active than uranium.”

The second stage of the research was to prove that an imponderable mass of an unknown element, too minute to yield an optical spectrum, could be the source of measurable and characteristic effects, whatever the composition of the compound of which it was a part. Mme. Curie showed the strength of her character: She foresaw the immense labor necessary in attempting to concentrate the active substance and the small means at her disposal; and yet she plunged into the adventure. Pierre shared her faith and abandoned—temporarily, he thought—his own research. He participated in the laborious chemical treatments as well as in the physical measurements of the products (of various concentrations), which were then compared with a sample of uranium.

It was already known that natural pitchblende is three or four times more active than uranium: after suitable chemical treatment the product obtained is 400 times more active and undoubtedly contains “a metal not yet determined, similar to bismuth… We propose to call it polonium, from the name of the homeland of one of us” (“Note” by M. and P. Curie, Comptes rendus…de l’Académie des sciences [18 July 1898]). However, the eminent spectroscopist Eugène Demarçay discerned no new lines; and it was necessary to procure more of the ore. Eduard Suess of the University of Vienna, a correspondent of the Institut de France, interceded with the Austrian government; and 100 kilograms were offered to the Curies. A third “Note” followed, signed also by Bémont, Pierre’s assistant at the école de Physique et Chimie: “We have found a second radioactive subtance, entirely different from the first in its chemical properties,…[which are] similar to those of barium” (Comptes rendus…de I’Académie des sciences [November 1898]). The substance was radium. This time Demarcay observed a new line in the spectrum; confirmation of both the technique of measurement and of the discoveries was in sight.

To make the confirmation irrefutable, still more primary material and treatments were necessary; and André Debierne assisted them. Mme. Curie wrote simply: “I submitted to a fractionated crystallization two kilograms of purified radium-bearing barium chloride that had been extracted from half a [metric] ton of residues of uranium oxide ore.” The currents reached 10^-7 amperes, and the substances obtained were 7,500 times more active than uranium (1899). A few months later they were 100,000 times more active.

The research not only accelerated but also became diversified. Pierre Curie studied the radiations; Marie tried to isolate the polonium, without success, and to determine the atomic weight of radium; Debierne discovered actinium. In Mme. Curie’s words:

None of the new radioactive substances has yet been isolated. To believe in the possibility of their isolation amounts to admitting that they are new elements. It is this opinion that has guided our work from the beginning: it was based on the evident atomic character of the radioactivity of the materials that were the object of our study… This tenacious property, which could not at all be destroyed by the great number of chemical reactions we carried out, which, in comparable reactions, always followed the same path, and manifested itself with an intensity clearly related to the quantity of inactive material retrieved,…must be an absolutely essential character of the material itself (1900).

They were reasoning as chemists: the physicist’s atom was still in limbo, although the connection between electricity and matter was being revealed, beginning with the electrons, which might be subatomic particles. J. J. Thomson located electrons in a solid sphere, while Jean Perrin imagined that their paths form a sort of miniature solar system (1901).

What slowed the interpretation of the phenomenon of radioactivity, as even Mme. Curie herself acknowledged, was the experimental datum that the radiant activity of uranium, thorium, radium, and probably also of actinium was constant. It is true that the activity of polonium was found to diminish, but Mme. Curie viewed this as an exception (1902). Although since January 1899 the Curies had considered, among other hypotheses, the instability of radioactive substances, their complete faith in experiment prevented them from following Rutherford along the same lines in 1903. If Rutherford and Soddy were right, every radioactive substance would destroy itself according to an exponential law but with a different period of decay. Thus the gaseous emanation of radium would result from the destruction of radium and would destroy itself, producing helium and other substances of a radioactive character. To account for the apparent stability of radium, Rutherford suggested a very long period of decay. This Mme. Curie was not ready to accept until experimental proof had been obtained that radium did not act “on its surroundings (nearby material atoms or the ether in a vacuum) in such a way that it produces atomic transformations…. Radium itself would then no longer be an element in the process of being destroyed.” However, in 1902 Mme. Curie had isolated a decigram of pure radium and, after great difficulties, determined its atomic weight for the first time, 225 (instead of the presently recognized value, 226). This success brought her the Berthelot Medal of the Académie des Sciences and, for the third time, the Gegner Prize (1902).

But Pierre Curie’s meager salary could not support the household and the research; Marie, even before defending her thesis (1903), took a position as lecturer in physics at the École Normale Supérieure in Sèvres (October 1900). There girls who had passed a competitive examination prepared for the agrégation. No woman had taught there before, and her lecture experiments assured her success.

Life was hard; then came international recognition of their work. Marie attended Pierre’s lecture in London at the Royal Institution in May 1903 and, on 5 November, shared with him the Humphry Davy Medal awarded by the Royal Society. The Nobel Prize for physics was awarded jointly to the Curies and to Henri Becquerel for the discovery of radioactivity (12 December 1903), although, because of weakened health, they did not go to Stockholm to receive it until 6 June 1905. This was followed by many other honors, including the Elliott Cresson Medal in 1909.

Rather than making them happy, this recognition overwhelmed the Curies with solicitations and correspondence that took too much of their time and drained their strength. The Curies denounced “the burden of fame"; their bicycle rides became less frequent and their vacations shorter. On 1 November 1904, a month before the birth of their daughter Eve (6 December), Marie was finally named Pierre’s assistant at the Faculté des Sciences, where she had long been working without pay. In 1906 Pierre, at last a member of the Académie des Sciences, presented a “Note” on the period of decay of polonium (140 days), to which Marie applied, for the first time. the Ruther-ford-Soddy exponential law. She proved, as had these two scientists, the release of helium. Nevertheless, many difficulties remained in interpreting the experimental results: the emanation (radon), induced radioactivity, and radioactive deposits that were more or less short-lived. The situation was further confused, theoretically, by the Curies’ observation that “Every atom of a radioactive body functions as a constant source of energy… which implies a revision of the principles of conservation.” The scientists pondered; the press exclaimed, “with radium the Curies have discovered perpetual motion!”

Mme. Curie then stated the policies of her research, to which she always remained faithful; push to the extreme the precision and rigor of measurement; obtain samples that are pure or of maximum concentration, even at the cost of handling enormous quantities of raw materials; and put forth general laws only in the complete absence of exceptions.

A French industrialist, Armet de L’Isle, confident that there was a future for medical and industrial applications of radium, constructed a factory in Nogent-sur-Marne, on the outskirts of Paris, for the extraction of radium from pitchblende residues. In 1904 Debierne installed a section there that prepared the materials needed in the laboratory. The Curies claimed no royalties and refused to take out any patents; they deliberately renounced a fortune, as they had declined a very favorable offer from the University of Geneva in 1900. They remained in France and gave free advice to anyone who asked for it.

Following Pierre’s death in April 1906, Marie became a different woman, even with her closest friends; she lost her gaiety and warmth and became distant. Her one thought was to continue: to raise her daughters, even to giving them their daily bath, a task she never entrusted to anyone else; and to go on in the laboratory as if Pierre were still there. Had he not once said to her, “Whatever happens, even if one were to be like a body without a soul, one must work just the same”?

The Ministry of public Education thought to do her a kindness by offering her a pension, as they had done for Pasteur’s widow. She refused; since she was still able to work, why deprive her of that? Surprised, the Faculty Council decided, unanimously, to maintain the chair of physics created for Pierre in 1904 and bestowed it on Marie (1 May 1906). She was confirmed in 1908. For the first time a woman taught at the Sorbonne.

Mme. Curie compelled recognition from her first lecture (5 November 1906), despite her timidity, the emotion she was concealing, her weak voice, and her monotone delivery. She made no introductory remarks, took no notice of the sightseers mingling with the students, and began her lecture with the last sentence that Pierre had spoken in that very place. In every demonstration experiment she watched the result with as much interest as if she did not already know it.

The vocabulary had grown considerably since her thesis; the dissymmetry between the negative charges (electrons), independent of any atomic material, and the positive charges, linked with the material atoms, was obvious. She introduced the terms “disintegration” and “transmutation” and described the advantages of the theory of radioactive transformations. Nevertheless, she included a reservation: “It seems useful to me not to lose sight of the other explanations of radioactivity that may be proposed.”

The smallness of the laboratory on the rue Cuvier permitted Marie to have only five or six researchers. Among them were Duane and Stark (two of the first Carnegie Scholars) in 1907 and Ellen Gleditsch in 1908. They fixed standards of measurement, verified that external agents have no effect on radioactivity, and studied the effect of emanation in the formation or condensation of clouds in closed chambers.

Mme. Curie’s treatise on radioactivity (1910) admitted, without reservations, the theory of transformations; and in a series of general articles written between 1911 and 1914 she described its consequences. By its nature the phenomenon of radioactivity substantiated the connection between matter and electricity; the causes of the explosion occurring each time an atom emits radiation and is transformed into another product remained to be discovered.⁶

As had pierre in 1903, Marie Curie declined the Legion of Honor (November 1910), asking only the means to work. Again like Pierre, she yielded to the pleas of their friends and presented herself to the Académie des Sciences. The leading candidate, on the basis of Lippmann’s recommendation, she was passed over (23 November 1911) for Branly after a slanderous newspaper campaign. She did not seem at all affected because she had been rejected for extrascientific reasons.

While the creation of a radium institute was in view, through an agreement between the Faculté des Sciences (basic research) and the Institute Pasteur (medical application), Mme. Curie raised the question of official standards for radium at the Radiology Congress in Brussels in September 1910.⁷ A standard was as necessary in research as it was in therapy. She was charged with preparing an ampule containing about twenty milligrams of radium metal, to be deposited with the International Bureau of Weights and Measures in Paris.⁸ The same Congress defined the curie (named in honor of Pierre), a new unit corresponding to the quantity of emanation (radon) from or in radioactive equilibrium with one gram of radium. (This definition was redefined in 1953 as the quantity of any radioactive nuclide in which the number of disintegrations per second is 3.700 × 10 ¹⁰.)

In 1911 the Nobel Prize for chemistry was awarded to Mme. Curie “for her services to the advancement of chemistry by the discovery of the elements radium and polonium,” the first time that a scientist had received such an award twice. The major portion of the prize money went directly to research and to friends. At this time her health was impaired; she left the house in Sceaux, 6 rue du Chemin-de-fer, where she had lived since 1906, and moved closer to her laboratory, to 36 quai de Bethune.

In 1913 Mme. Curie had the pleasure of inaugurating the radioactivity pavilion in Warsaw. In January 1914 the Conseil de I’Institut du Radium was formed; she was a member, along with Appell, dean of the Faculté de Sciences; Lippmann, assistant to Appell; and the representatives of the Institut Pasteur, its director, Émile Roux and Prof. Claude Regaud. The building was almost finished by July. Pretending not to know of Mme. Curie’s lack of concern with financial matters, the administration constantly made difficulties for her, whether it was a question of dealing with industry or the Service de Mesure, taking inventory of supplies, or importing ores that were subject to taxation.

When World War I broke out, Mme. Curie, after having put her precious gram of radium in safekeeping in Bordeaux (3–4 September), aided the army; the radiological apparatus already used by civilian surgeons was being ignored by military doctors. With the aid of private gifts, she equipped the ambulances that she accompanied to the front lines with portable X-ray apparatus and, on 28 July 1916, she obtained a driver’s license in order not to be dependent on a chauffeur. The Red Cross (Union des Femmes Françaises) officially made her the head of its Radiological Service, and the Patronage National des Blessés allocated her funds to increase the number of radiological installations to 140. With her daughter Irène, who became her first experimental assistant, and Marthe Klein (later Mme. Pierre Weiss), she created accelerated courses in radiology for medical orderlies and taught doctors the new methods of locating foreign objects in the human body. Later (1920) she wrote La radiologie et la guerre from her wartime notes.

The Radium Institute began to function. In 1918 Mme. Curie reported to the Committee on Radioactive Substances of the Ministry of Munitions on the radioelements, their role, and their applications. With the return of peace, she finally installed herself at the Institute. Irène, officially named as her préparateur, assisted her particularly in the special courses designed for members of the American Expeditionary Force.

American women were so moved by Mme. Curie’s talent and generosity that they opened a national subscription to offer her a gram of radium on the appeal of a journalist, Mrs. Meloney. In May 1921 Mme, Curie made a triumphal visit to the United States with her daughters; she received from President Harding the gold key to the case holding the precious substance. Despite her fatigue and her distaste for display, Mme. Curie was deeply moved by this gesture, and perhaps even more so when it was repeated in 1929 for the benefit of the radium therapy services of Warsaw. The inauguration, on 29 May 1932, of the Maria Sklodowska-Curie Radium Institute (which provided facilities for the treatment of patients) was the occasion for her last trip outside France.

The creation of the Curie Foundation (1920), which was empowered to receive private gifts, and her election to the Académic de Médicine in 1922 assured Mme. Curie contact with the medical profession for two goals that Pierre had cherished: the development of what had come to be called “curietherapy” and the establishment of safety standards for workers. (See her book Pierre Curie.)

She was invited by Sir Eric Drummond, secretary general of the League of Nations, to sit on the International Commission for Intellectual Cooperation (17 May 1922) and became its vice-president. She concerned herself with increasing the number of available postgraduate scholarships and with requiring from authors a résumé of their scientific memoirs in order to speed the publication of abstracts. However, the length of discussions on minor subjects, such as standardizing the format of periodicals, sometimes exasperated her.

Her daughter Eve (later Mrs. Henry Labouisse), who devoted herself to literature and music, sometimes took her mother to the theater; Mme. Curie interested herself in all creative endeavors. She followed the work of Sacha Pitoëff (in the 1920’s and 1930’s) and fostered that of the choreographer Loië Fuller (in the early 1900’s). During vacations she swam and took long nature walks. Mme. Curie closely supervised the work of her collaborators at the Radium Institute. They were of many nationalities, by 1933 numbering seventeen, and their work led from success to success. Iréne Curie completed a thesis on the α rays of polonium in 1925. Then Fernand Holweck, using a pump of his own design, studied X Rays in the region of maximal absorption and established the relationship between those rays and light. Although it had long been appreciated that X rays and light are of the same nature, no one had succeeded in obtaining a sufficiently complete vacuum to detect X rays of long wavelength. Fernand Holweck’s pump, which depended on a technique for soldering glass to metal, made this possible. Salomon Rosenblum, a Curie Scholar, employed Bellevue’s powerful electromagnet and discovered the fine structure of the spectrum of the α rays. The discovery of artificial radioactivity by Irène Curie and her husband, Frédéric Joliot, followed in 1933. It was like an echo of Mme. Curie’s first ideas on the influence of the radioelements on their environment. At the same time that she was composing a second treatise on radioactivity, Mme. Curie, with the help of Mme. Cotelle and Mlle. Chamié, prepared derivatives of actinium that had not yet been isolated, sometimes staying in the laboratory all night.

Her health declined, but she never spoke of it and grumbled about the interruptions in her work imposed by her doctors. The twenty-fifth anniversary of the discovery of radium was celebrated at the Sorbonne between two of her cataract operations: she had four between 1923 and 1930. She also suffered from lesions on her fingers in 1932, the result of handling radium. She was obliged to enter a nursing home in Paris on 6 June 1934; and then, weakened, she was taken to a sanatorium in the French Alps on 29 June. She did not return.

Of all the honors Mme. Curie received, of all the tributes that were paid her, the one that best fits her personality is a book dedicated to her memory by the French Society of Physics on the centenary of her birth: Colloquium on Medium and Heavy Nuclei. The following generations have taken up the torch that she alone had carried for twenty-eight years.

NOTES

1. The house in which Marie was born, in which she lived for only several months, became a laboratory bearing her name.

2. First on rue Flatters, then boulevard de Port-Royal, and finally 11 rue des Feuillantines, in the Latin Quarter.

3. A plaque is affixed there honoring the Curies.

4. A plaque recalls their stay there.

5. “Note,” in Comptesrendus… del’Académic des sciences(23 Nov. 1896).

6. Communication of Mme. Curie to the Conseil de Physique, Solvay (Brussels, 1911).

7. She had discovered a method of determining the quantity of radium from the radiation emitted (Le radium, 7, 65).

8. Thanks to generous donations, she was compensated for the material she hérself had given for this purpose.

BIBLIOGRAPHY

I Original Works. All of Marie Curie’s original memories and a few of her general articles have been collected in a single volume by Irène Joliot-Curie: Oeuvres de Marie Sklodowska-Curie(Warsaw, 1954). The following works in particular should be mentioned: Recherches sur les substances radioactives, 2nd ed.(Paris, 1904), her thesis; Les théories modernes relatives à l’électriciteé et à la matière, the opening lecture of her physics course, 5 Nov. 1906; “Les mesures en radioactivité et l’étalon du radium.” in Journalde physique, 2 (1912), 715; Sur les rayonnements des corps radioactifs (Paris, 1913); and “Les radio-éléments et leur classification,” in Revue du mois (1914).

See also the first Traité de radioactivité, 2 vols. (Paris, 1910); L’isotope et les éléments isotopes (Paris, 1922–1923); Pierre Curie (Paris, 1924), the American ed. of which (New York, 1923) includes a biography of Marie Curie; and Radioactivité, posthumous ed. prepared by Iréne and Frédéreacute;c Joliet, 2 vols. (paris1935).

II. Secondary Literature Among the innumerable articles and books on Marie Curie are J. Christie, “The Discovery of Radium,” in journal of the Franklin Institute, 167, no.5 (May 1909); B. Szilard, Frau Curie and ihr Werk,” in Chemikerzeitung (1911)B. Harrow, Eminent chemists of our Time (New York) Hamilton Foley, “Madame Curie, the Nation’s Guest” and “the Sources of Radium,” in Bulletin of the Pan-American union (July 1921); Debierne, “Le 25^e anniversaire de sa découverte du radium, in Chimie et industrie (Mar 1924) Le radium célébration du 25^e anniversaire de sa découvere (Paris, 1924); C. Regaud, Marie Sklodowska Curie (Paris, 1934); Lord Rutherford, “Marie Curie in Nature (21 July 1934) L. Wertenstien, in Nature, 141 (18 June 1938), 1079–1081; Eve Curie, Madame Curie (Paris 1939), English trans. by Vincent Sheen (New York -London, 1939); Iréne Joliot-Curie, “Marie Curie, ma mère, “in Europe, 108 (Dec.1954); and Eugénie Cotton, Les Curie et la radioactivité (Paris, 1963).

The ceremonies commemorating the centenary of Mme. Curie’s birth have given rise to numerous publications. The catalog of L’exposition Pierre et Marie Curie (Paris, 1967) contains an exhaustive chronology of the events at the exposition. In addition, the following may be consulted: the special number of the Annals de l’Université (Paris, 1968); Centenary Lectures, A. I. E. A., Warsaw, 17–20 October 1967 (Vienna 1968) and the articles of Marcel Guillot in Nuclear physics, A103 (1967), 1–8; and J. Hurwic, in Colloque Cl, 29, supp. to Journal de physique (Jan. 1968), followed by the reprinting of Mme. Curie’s first “Note.”

Adrienne R. Well

Curie, Marie (1867-1934)

Polish-born French physicist

Marie Curie was the first woman to win a Nobel Prize, and one of very few scientists ever to win that award twice. In collaboration with her physicist-husband Pierre Curie , Marie Curie developed and introduced the concept of radioactivity to the world. Working in primitive laboratory conditions, Curie investigated the nature of high-energy rays spontaneously produced by certain elements, and isolated two new radioactive elements, polonium and radium. Her scientific efforts also included the application of x rays and radioactivity to medical treatments.

Curie was born to her two-schoolteacher parents in Warsaw, Poland. Christened Maria Sklodowska, she was the fourth daughter and fifth child in the family. By the age of five, she had already begun to suffer deprivation. Her mother Bronislawa had contracted tuberculosis and assiduously avoided kissing or even touching her children. By the time Curie was 11, both her mother and her eldest sister Zosia died, leaving Marie an avowed atheist. Curie was also an avowed nationalist (like the other members in her family), and when she completed her elementary schooling, she entered Warsaw's "Floating University," an underground, revolutionary Polish school that prepared young Polish students to become teachers.

Curie left Warsaw at the age of 17, not for her own sake but for that of her older sister Bronya. Both sisters desired to acquire additional education abroad, but the family could not afford to send either of them, so Marie took a job as a governess to fund her sister's medical education in Paris. At first, she accepted a post near her home in Warsaw, then signed on with the Zorawskis, a family who lived some distance from Warsaw. Curie supplemented her formal teaching duties there with the organization of a free school for the local peasant children. Casimir Zorawski, the family's eldest son, eventually fell in love with Curie and she agreed to marry him, but his parents objected vehemently. Stunned by her employers' rejection, Curie finished her term with the Zorawskis and sought another position. She spent a year in a third governess job before her sister Bronya finished medical school and summoned her to Paris.

In 1891, at the age of 24, Curie enrolled at the Sorbonne and became one of the few women in attendance at the university. Although Bronya and her family back home were helping Curie pay for her studies, living in Paris was quite expensive. Too proud to ask for additional assistance, she subsisted

on a diet of buttered bread and tea, which she augmented sometimes with fruit or an egg. Because she often went without heat, she would study at a nearby library until it closed. Not surprisingly, on this regimen she became anemic and on at least one occasion fainted during class.

In 1893, Curie received a degree in physics , finishing first in her class. The following year, she received a master's degree, this time graduating second in her class. Shortly thereafter, she discovered she had received the Alexandrovitch Scholarship, which enabled her to continue her education free of monetary worries. Many years later, Curie became the first recipient ever to pay back the prize. She reasoned that with that money, yet another student might be given the same opportunities she had.

Friends introduced Marie to Pierre Curie in 1894. The son and grandson of doctors, Pierre had studied physics at the Sorbonne; at the time he met Marie, he was the director of the École Municipale de Physique et Chimie Industrielles. The two became friends, and eventually she accepted Pierre's proposal of marriage. Their Paris home was scantily furnished, as neither had much interest in housekeeping. Rather, they concentrated on their work. Pierre Curie accepted a job at the School of Industrial Physics and Chemistry of the City of Paris, known as the EPCI. Given lab space there, Marie Curie spent eight hours a day on her investigations into the magnetic qualities of steel until she became pregnant with her first child, Irene, who was born in 1897.

Curie then began work in earnest on her doctorate. Like many scientists, she was fascinated by French physicist Antoine-Henri Becquerel's discovery that the element uranium emitted rays that contained vast amounts of energy. Unlike Wilhelm Röntgen's x rays, which resulted from the excitation of atoms from an outside energy source, the "Becquerel rays" seemed to be a naturally occurring part of the uranium ore. Using the piezoelectric quartz electrometer developed by Pierre and his brother Jacques, Marie tested all the elements then known to see if any of them, like uranium, caused the nearby air to conduct electricity . In the first year of her research, Curie coined the term "radioactivity" to describe this mysterious force. She later concluded that only thorium and uranium and their compounds were radioactive.

While other scientists had also investigated the radioactive properties of uranium and thorium, Curie noted that the minerals pitchblende and chalcolite emitted more rays than could be accounted for by either element. Curie concluded that some other radioactive element must be causing the greater radioactivity. To separate this element, however, would require a great deal of effort, progressively separating pitchblende by chemical analysis and then measuring the radioactivity of the separate components. In July, 1898, she and Pierre successfully extracted an element from this ore that was even more radioactive than uranium; they called it polonium in honor of Marie's homeland. Six months later, the pair discovered another radioactive substance—radium—embedded in the pitchblende.

Although the Curies had speculated that these elements existed, to prove their existence they still needed to describe them fully and calculate their atomic weight. In order to do so, Curie needed an abundant supply of pitchblende and a better laboratory. She arranged to get hundreds of kilograms of waste scraps from a pitchblende mining firm in her native Poland, and Pierre Curie's EPCI supervisor offered the couple the use of a laboratory space. The couple worked together, with Marie performing the physically arduous job of chemically separating the pitchblende and Pierre analyzing the physical properties of the substances that Marie's separations produced. In 1902, the Curies announced that they had succeeded in preparing a decigram of pure radium chloride and had made an initial determination of radium's atomic weight. They had proven the chemical individuality of radium.

Pierre Curie's father had moved in with the family and assumed the care of their daughter, Irene, so the couple could devote more than eight hours a day to their work. Pierre Curie's salary, however, was not enough to support the family, so Marie took a position as a lecturer in physics at the École Normal Supérieure; she was the first woman to teach there. In the years between 1900 and 1903, Curie published more than she had or would in any other three-year period, with much of this work being co-authored by Pierre Curie. In 1903, Curie became the first woman to complete her doctorate in France, summa cum laude.

The year Curie received her doctorate was also the year she and her husband began to achieve international recognition for their research. In November, the couple received England's prestigious Humphry Davy Medal, and the following month Marie and Pierre Curie—along with Becquerel—received the Nobel Prize in physics for their efforts in expanding scientific knowledge about radioactivity. Although Curie was the first woman ever to receive the prize, she and Pierre declined to attend the award ceremonies, pleading they were too tired to travel to Stockholm. The prize money from the Nobel, combined with that of the Daniel Osiris Prize—which she received soon after—allowed the couple to expand their research efforts. In addition, the Nobel bestowed upon the couple an international reputation that furthered their academic success. The year after he received the Nobel, Pierre Curie was named professor of physics of the Faculty of Sciences at the Sorbonne. Along with his post came funds for three paid workers, two laboratory assistants and a laboratory chief, stipulated to be Marie. This was Marie's first paid research position.

In 1904, Marie gave birth to another daughter. Despite the fact that both Pierre and Marie frequently suffered adverse effects from the radioactive materials with which they were in constant contact, their infant daughter was born healthy. The Curies continued their work regimen, taking sporadic vacations in the French countryside with their two children. They had just returned from one such vacation when in April 1906, tragedy struck; while walking in the congested street traffic of Paris, Pierre was run over by a heavy wagon and killed.

A month after the accident, the University of Paris invited Curie to take over her husband's teaching position. Upon acceptance she became the first woman to ever receive a post in higher education in France, although she was not named to a full professorship for two more years. During this time, Curie came to accept the theory of English physicists Ernest Rutherford and Frederick Soddy that radioactivity was caused by atomic nuclei losing particles, and that these disintegrations caused the transmutation of an atomic nucleus into a different element. It was Curie, in fact, who coined the terms disintegration and transmutation.

In 1909, Curie received an academic reward that she had greatly desired: the University of Paris drew up plans for an Institut du Radium that would consist of two branches, a laboratory to study radioactivity—which Curie would run—and a laboratory for biological research on radium therapy, to be overseen by a physician. It took five years for the plans to come to fruition. In 1910, however, with her assistant André Debierne, Curie finally achieved the isolation of pure radium metal, and later prepared the first international standard of that element.

Curie was awarded the Nobel Prize again in 1911, this time "for her services to the advancement of chemistry by the discovery of the elements radium and polonium," according to the award committee. The first scientist to win the Nobel twice, Curie devoted most of the money to her scientific studies. During World War I, Curie volunteered at the National Aid Society, then brought her technology to the war front and instructed army medical personnel in the practical applications of radiology. With the installation of radiological equipment in ambulances, for instance, wounded soldiers would not have to be transported far to be x-rayed. When the war ended, Curie returned to research and devoted much of her time to her work.

By the 1920s, Curie was an international figure; the Curie Foundation had been established in 1920 to accept private donations for research, and two years later the scientist was invited to participate on the League of Nations International Commission for Intellectual Cooperation. Her health was failing, however, and she was troubled by fatigue and cataracts. Despite her discomfort, Curie made a highly publicized tour of the United States in 1921. The previous year, she had met Missy Meloney, editor of the Delineator, a woman's magazine. Horrified at the conditions in which Curie lived and worked (the Curies had made no money from their process for producing radium, having refused to patent it), Meloney proposed that a national subscription be held to finance a gram of radium for the institute to use in research. The tour proved grueling for Curie; by the end of her stay in New York, she had her right arm in a sling, the result of too many too strong handshakes. However, with Meloney's assistance, Curie left America with a valuable gram of radium.

Curie continued her work in the laboratory throughout the decade, joined by her daughter, Irene Joliot-Curie, who was pursuing a doctoral degree just as her mother had done. In 1925, Irene successfully defended her doctoral thesis on alpha rays of polonium, although Curie did not attend the defense lest her presence detract from her daughter's performance. Meanwhile, Curie's health still continued to fail and she was forced to spend more time away from her work in the laboratory. The result of prolonged exposure to radium, Curie contracted leukemia and died in 1934, in a nursing home in the French Alps. She was buried next to Pierre Curie in Sceaux, France.

See also History of exploration III (Modern era)

CURIE, MARIE

CURIE, MARIE (1867–1934), Polish physicist and chemist.

Maria Sklodowska was born in Warsaw, Poland, the youngest of six children. Maria's father taught mathematics and physics and her mother ran a private girls' school. Although Maria was obviously a brilliant student, advanced studies were not accessible to women in Poland, then a part of the Russian Empire. Knowing that their family could not afford to send them to study abroad, Maria and her sister Bronya agreed that Maria would work as a governess so that Bronya could study medicine in Paris. When Bronya graduated, Maria would join her and enroll at the Sorbonne.

In 1891, Maria Sklodowska moved to Paris to study mathematics and physics. While a student at the Sorbonne, she adopted the French form of her name. Within three years she had earned master's degrees in physics and mathematics, placing first among the candidates in physics and second in mathematics. Before meeting French physicist Pierre Curie (1859–1906), Sklodowska planned to earn a teaching certificate and return to Poland. One year later, in July 1895, Marie and Pierre Curie were married in a simple civil ceremony. Marie Curie gave birth to Irène in 1897 and Ève in 1904.

the discovery of radioactivity, polonium, and radium

In 1896, when French physicist Antoine Henri Becquerel (1852–1908) attempted to determine whether X-rays, which had been discovered the previous year by the German physicist Wilhelm Conrad Roentgen (1845–1923), were related to

the phenomenon known as luminescence, he discovered a new type of radiation emitted by uranium salts. Although Becquerel's discovery attracted little attention at first, Marie Curie decided that a systematic investigation of "Becquerel rays" would be a suitable topic for her doctoral research. After investigating the radiation released by uranium compounds, Curie systematically tested other materials to see which elements might give off similar radiation. Only thorium and uranium produced spontaneous radioactivity, but certain natural ores, including pitchblende and chalcolite, seemed to give off more radiation than predicted by measurements of their uranium and thorium content. Curie concluded that these ores must contain unknown elements that were intrinsically more radioactive than uranium and thorium.

From her initial studies of uranium and thorium, Marie Curie arrived at a remarkable theoretical insight, one that challenged long-held beliefs about the nature of the atom. Curie realized that the strength of radiation was a function of the amount of uranium or thorium in a sample, and it was independent of the specific chemical compound being studied. Ordinarily, an element exhibits very different chemical and physical properties when it combines with other elements to form chemical compounds. Curie concluded that the release of radioactivity was an intrinsic property of the interior of the atom, rather than a function of the arrangement of atoms in a molecule. It was Marie Curie who introduced the term radioactivity ("ray action").

In 1898, the Curies announced the existence of two new radioactive elements, which they called polonium and radium. These elements were orders of magnitude stronger sources of radioactivity than uranium and thorium, but they were present in crude ores in very minute amounts. In order to isolate sufficient quantities of the new elements for the determination of their chemical properties and atomic weights, the Curies needed tons of pitchblende. (A ton of uranium ore contains about one ounce of radium.) Marie Curie's isolation of minute quantities of radium took years of extremely arduous labors under difficult conditions.

While processing tons of pitchblende, the Curies worked in a large, unoccupied shed. Friedrich Wilhelm Ostwald (1853–1932), an eminent German chemist, described it as more like a stable or a potato shed than a laboratory. Marie Curie later said that the years she and Pierre spent in that unheated, drafty, leaky, malodorous shed were the best and happiest of their lives. She also treasured memories of coming back to the shed at night and seeing their partially purified preparations glowing in the dark with a lovely pale blue light. Nevertheless, the four years of drudgery involved in the isolation of radium left both of the Curies perpetually ill and fatigued from what was later called radiation sickness. Marie Curie presented her findings as a doctoral dissertation in June 1903. Members of her thesis committee commended her discoveries and theoretical insights as probably the most significant scientific contributions ever made in a doctoral dissertation. For her work on radium, Marie Curie, the first woman in Europe to receive a doctorate in science, was awarded the degree of Doctor of Science "with great distinction."

The potential uses of radium, especially in medicine, were quickly recognized and entrepreneurs built factories for large-scale production. The Curies generously supplied samples of radium to fellow researchers and gave advice about its preparation to industrialists. Because they believed that scientific knowledge should be shared with the world at large, the Curies did not patent their discoveries. During the last decades of her life, Marie Curie apparently had some regrets about this decision. Years of arduous fund-raising activities forced her to realize how much her work would have been expedited by a reliable source of funding. She actively supported a resolution developed by the Commission on Intellectual Cooperation of the League of Nations to protect the intellectual property rights of scientists and inventors.

In 1903 the Academy of Sciences debated nominating Becquerel and Pierre Curie for the Nobel prize in Physics. Warned about these proceedings by a colleague, Pierre Curie made it clear that a Nobel prize for research in radioactivity that failed to acknowledge Marie would be a travesty. Although both Curies shared the 1903 Nobel prize in Physics with Becquerel, they were too ill from radiation sickness to attend the award ceremony. Despite their poor health and constant fatigue, the Curies did not believe that radiation could have a detrimental effect on human health. Researchers at the time handled radioactive substances without any precautions. In 1905, the Curies made the trip to Stockholm, where Pierre delivered the Nobel Lecture. The Nobel Institution was pleased by the universal interest in the romantic story of the Curies, but Marie was intensely disturbed by the media attention and invasion of privacy.

In 1904, Pierre Curie was finally granted an appointment to a professorship at the Sorbonne, and Marie was given the title Chief of the Laboratory, as well as a small salary. When university officials offered to nominate Pierre for the prestigious Legion of Honor, he refused the award and said he would rather have a laboratory. Tragically, Pierre died before the laboratory was completed. On 19 April 1906, he was struck and killed by a horse-drawn cart while crossing the street. Marie Curie was devastated, but when she was offered a pension she refused it, insisting that she wanted to work. Marie Curie took over Pierre's courses, thus becoming the first woman to teach at the Sorbonne. Nevertheless, it took two years for the university to officially appoint her as Professor. She also became Director of the Curie Laboratory in the Radium Institute of the University of Paris.

the nobel prize in chemistry

When Marie Curie won the 1911 Nobel prize in Chemistry for the discovery of radium and polonium, and the isolation and characterization of pure radium, she became the first person to receive two Nobel prizes. In her Nobel Lecture, Curie clearly enunciated her own ideas and discoveries, as well as her unique collaboration with Pierre Curie. Despite her remarkable scientific achievements, the year in which Curie received her second Nobel prize was one of great distress. She was attacked in the right-wing French press for becoming a candidate for the Academy of Sciences and her relationship to Paul Langevin (1872–1946), a French physicist, who was married and the father of four children. The medical work carried out by Curie and her daughter Irène during World War I was significant in restoring her place as a muchloved icon in French history. Curie worked ceaselessly to equip vehicles that acted as mobile field hospitals, as well as X-ray installations near the battlefront. She also trained people to use diagnostic X-ray technology.

After the end of World War I in 1918, Curie's Radium Institute became France's premier research laboratory, but Curie had to devote a lot of time and energy to the task of raising funds for the Institute. Tours of the United States in 1921 and 1929, supported by the Federation of American Women's Clubs, raised enough money to purchase radium for Marie Curie's Institute in France and for a Radium Institute in Warsaw. Marie Curie was the author or co-author of many scientific articles and books including Investigations on Radioactive Substances (1904), Treatise on Radioactivity (1910), Radioactivity and the War (1921), Pierre Curie (including autobiographical notes by Marie Curie, 1923), Radioactivity (1935), and a collection of Pierre's work (1908).

Marie Curie died of leukemia on 4 July 1934. In keeping with her desire for privacy, she was buried next to Pierre Curie in a simple private ceremony. Albert Einstein (1879–1955) paid tribute to Marie Curie as "the only person to be uncorrupted by fame." On 20 April 1995, the bodies of Marie and Pierre Curie were ceremoniously transferred to the Panthéon in Paris. French President François Mitterrand (1916–1996) sponsored this honor as a way of acknowledging the equality of women and men. Marie Curie was the first woman to receive this honor on her own merit.

See alsoChemistry; France; Science and Technology.

bibliography

Primary Sources

Curie, Marie. Recherches sur les Substances Radioactives. Paris, 1903. Marie Curie's doctoral dissertation, presented at the Sorbonne in 1903.

——. Pierre Curie. Translated by Charlotte and Vernon Kellogg. New York, 1923. Only the American edition received Marie Curie's permission to include her autobiographical notes.

——. Oeuvres de Marie Sklodowska Curie. Edited by Irène Joliot-Curie. Warsaw, 1954.

Secondary Sources

Brush, Stephen G. "Women in Physical Science: From Drudges to Discoverers." The Physics Teacher 23 (January 1985): 11–19. This classic article explores the "Marie Curie Syndrome" and the negative effects caused by stereotypical descriptions of female scientists.

Curie, Eve. Madame Curie, A Biography. Translated by Vincent Sheean. New York, 1937. Intensely personal, moving biography, published by her daughter only three years after Curie's death. A new edition, with a preface by Mitchell Wilson, was published in London, 1968.

Giroud, Françoise. Marie Curie, a Life. Translated by Lydia Davis. New York, 1986. Not intended as a scholarly biography but as a way of presenting Giroud's own interpretation of Curie's personality and her role in the history of science and France.

Goldsmith, Barbara. Obsessive Genius: The Inner World of Marie Curie. New York, 2005. A biography that emphasizes personal relationships rather than science.

McGrayne, Sharon Bertsch. Nobel Prize Women in Science: Their Lives, Struggles, and Momentous Discoveries. Secaucus, N.J., 1993. Allows readers to compare the work and world of Marie Curie with other women who became Nobel Laureates.

Pflaum, Rosalynd. Grand Obsession: Madame Curie and Her World. New York, 1989. Emphasizes the exhausting and laborious nature of the work conducted by Marie and Pierre Curie, as well as their daughter Irène and son-inlaw Frédéric Joliot. Also explains the technical aspects of their work in clear and accessible terms.

Quinn, Susan. Marie Curie: A Life. London, 1995. Uses newly available archival material to provide new insights into the emotional life of the legendary scientist.

Reid, Robert. Marie Curie. London, 1974. This comprehensive and well-documented biography was the basis for the BBC five-part miniseries Marie Curie (1978).

Lois N. Magner

Marie Curie

Born: November 7, 1867
Warsaw, Poland
Died: July 4, 1934
Sancellemoz, France
Polish-born French physicist

The Polish-born French physicist Marie Curie invented the term "radioactivity" and discovered two elements, radium and polonium. Curie was not only the first woman to win the Nobel Prize in Physics, but when she won the Nobel Prize in Chemistry, she became the first person ever to win the Nobel Prize twice.

Early life

Marie Sklodowska Curie was born in Warsaw, Poland, on November 7, 1867, the youngest of five children of Wladislaw and Bronislava Boguska Sklodowska. After her father lost his job, the family struggled and was forced to take borders (renters) into their small apartment. Religious as a child, Curie rejected her faith after her sister died of typhus (a severe fever) in 1876. Two years later she lost her mother to tuberculosis, a terrible disease that attacks the lungs and bones.

Marie was a brilliant student, gaining a gold medal upon completing her secondary education in 1883. As girls could not attend universities in Russian-dominated Poland, Marie spent a year in the country with friends at her father's suggestion. Upon returning to her father's house in Warsaw the next summer, she began to earn her living through private tutoring. She also became associated with the "Floating University," a group of young men and women who tried to quench their thirst for knowledge in secret sessions.

In early 1886 Marie accepted a job as governess (private educator) with a family living in Szczuki, Poland, but the intellectual loneliness she experienced there only solidified her determination to somehow achieve her dream of becoming a university student. One of her sisters, Bronya, was already in Paris, France, successfully passing the examinations in medicine. In September 1891 Marie moved in with her sister in Paris.

Work in Paris

When classes began at the Sorbonne in Paris in early November 1891, Marie enrolled as a student of physics. By 1894 she was desperately looking for a laboratory where she could work on her research project, the measurement of the magnetic properties of various steel alloys (metal mixtures). Acting upon a suggestion, she visited Pierre Curie at the School of Physics and Chemistry at the University of Paris. In 1895 Pierre and Marie were married, thus beginning a most extraordinary partnership in scientific work.

By mid-1897 Curie's scientific achievements were two university degrees, a fellowship (a scholarship), and a monograph (published paper) on the magnetization of tempered steel. The couple's first daughter, Irène, had just been born, and it was then that the Curies turned their attention to the mysterious radiation from uranium recently discovered by Antoine Henri Becquerel (1852–1908). It was Marie's hunch that the radiation was an atomic property, and therefore had to be present in some other elements as well. Her search soon established the fact of a similar radiation from thorium, and she invented the historic word "radioactivity" (the spontaneous release of radium).

While searching for other sources of radioactivity, the Curies had turned their attention to pitchblende, a mineral well known for its uranium content. To their immense surprise the radioactivity of pitchblende far exceeded the combined radioactivity of the uranium and thorium contained in it. From their laboratory two papers reached the Academy of Sciences within six months. The first, read at the meeting of July 18, 1898, announced the discovery of a new radioactive element, which the Curies named polonium after Marie's native country. The other paper, announcing the discovery of radium, was read at the December 26 meeting.

From 1898 to 1902 the Curies converted several tons of pitchblende, but it was not only the extremely precious centigrams of radium that rewarded their superhuman efforts. The Curies also published, jointly or separately, during those years a total of thirty-two scientific papers. Among them, one announced that diseased, tumor-forming cells were destroyed faster than healthy cells when exposed to radium.

Recognition

In November 1903 the Royal Society of London gave the Curies one of its highest awards, the Davy Medal. A month later followed the announcement from the Nobel Foundation in Stockholm, Sweden, that three French scientists, A. H. Becquerel and the Curies, were the joint recipients of the Nobel Prize in Physics for 1903. Finally, even the academics in Paris began to stir, and a few months later Marie was appointed director of research at the University of Paris.

In December 1904 their second daughter, Ève, was born. The next year brought the election of Pierre to the Academy of Sciences and their travel to Stockholm, where, on June 6, he delivered the Nobel Prize lecture, which was in fact their joint address. Pierre ended his speech with the double-edged impact on mankind of every major scientific advance. Pierre said that he believed "mankind will derive more good than harm from the new discoveries."

End of an era

The joyful time for this husband-and-wife team would not last long. On the rainy mid-afternoon of April 19, 1906, Pierre was run down by a heavy carriage and killed instantly. Two weeks later the widow was asked to take over her late husband's post. Honors began to pour in from scientific societies all over the world on a woman left alone with two small children and with whom the gigantic task of leadership in radioactivity research was now left. In 1908 she edited the collected works of her late husband, and in 1910 she published her massive Traité de radioactivité. Shortly after this work Curie received her second Nobel Prize, this time in chemistry. Still, Curie was unable to win over the Academy of Sciences, who once again denied her membership.

Curie devoted much of her time during World War I (1914–18) to equipping automobiles in her own laboratory, the Radium Institute, with x-ray (Roentgen) apparatus to assist the sick. It was these cars that became known in the war zone as "little Curies." By the end of the war Curie was past her fiftieth year, with much of her physical energy already spent—along with her savings, which she had patriotically invested in war bonds. But her dedication was inexhaustible. The year 1919 witnessed her installation at the Radium Institute, and two years later her book La Radiologie et la guerre was published. In it she gave a most informative account of the scientific and human experiences gained for radiology (the use of radiation) during the war. At the end of the war, her daughter Irène, a physicist, was appointed as an assistant in her mother's laboratory.

Shortly afterward, a momentous visit took place in the Radium Institute. The visitor was Mrs. William B. Meloney, editor of a leading magazine in New York and representative of the countless women who for years had found in Curie their ideal and inspiration. A year later Meloney returned to tell Curie that a nationwide subscription in America had produced the sum of one hundred thousand dollars, which was needed to purchase a gram of radium for her institute. She was also asked to visit the United States with her daughters and collect the precious gift in person. Her trip was an absolute triumph. In the White House, President Warren G. Harding (1865–1923) presented her with the golden key to the little metal box containing the radium.

Later years

On questions other than scientific, Curie rarely uttered public comment of any length. One of the exceptions was her statement at a conference in 1933 on "The Future of Culture." There she rallied to the defense of science, which several panelists held responsible for the dehumanization of modern life. "I am among those," she emphasized, "who think that science has great beauty. A scientist in his laboratory is not only a technician; he is also a child placed before natural phenomena which impress him like a fairy tale. We should not allow it to be believed that all scientific progress can be reduced to mechanism, machines, gearings, even though such machinery also has its own beauty."

The most heartwarming experience of the last phase of Curie's life was probably the marriage of her daughter Irène in 1926 to Frédéric Joliot (later Joliot-Curie), the most gifted assistant at the Radium Institute. Before long it was evident to her that their union would closely resemble her own marvelously creative partnership with Pierre Curie.

She worked almost to the very end and succeeded in completing the manuscript of her last book, Radioactivité. In the last years her younger daughter, Ève, was her great support. Ève was also her mother's faithful companion when, on July 4, 1934, Curie died in Sancellemoz, France. Albert Einstein (1879–1955) once said, "Marie Curie is, of all celebrated beings, the only one whom fame has not corrupted."

For More Information

Quinn, Susan. Marie Curie: A Life. New York: Simon & Schuster, 1995.

Senior, John E. Marie & Pierre Curie. Gloucestershire, England: Sutton Pub., 1998.

Curie, Marie

Marie Curie's (1867-1934) amazing persistence in the face of many research obstacles is enough to commend her to historical fame. Her contribution to the field of medicine is overshadowed by her initial discovery of two radioactive elements, polonium and radium. She used these discoveries to help develop therapies for disease.

Curie was born Marie Sklodowska in Warsaw, Poland, in 1867. Her mother was principal of a local girls' school, and her father was a physics teacher. Curie excelled at school and was encouraged in her studies by her parents. Unfortunately, Poland was under Russian rule, and Russian authorities did not want educated Poles to become politically active and possibly lead a rebellion. As a result, Curie was not allowed to go to college in Poland. After working for several years, she left Poland for France, where she enrolled at the Sorbonne in 1891. Her meager savings barely covered tuition and rent for her one-room apartment, and she often went for long periods without food and once fainted from hunger during class. Her enthusiasm for learning did not waver, however, and in 1893 she received a degree in physics, graduating first in her class. While pursuing a second degree, she met Pierre Curie, who had made a name for himself by discovering piezoelectricity a few years earlier. The couple was married on July 26, 1895.

Soon after the marriage, Pierre earned his doctorate. Marie was still working toward her dissertation, but had not chosen a topic. French physicist Antoine Henri Becquerel (1852-1908; first scientist to experiment with radioactivity) had just discovered that uranium salts emitted (gave off) energy. At his suggestion, Marie set out to find other substances that emitted such rays. It was known that the ore pitchblende possessed properties similar to those of uranium, so the Curies chose this ore as the starting point for their research.

Research Leads to Results

Within the pitchblende the Curies detected the presence of a substance that was much more radioactive (a word Marie Curie had coined, or made up) than even pure uranium. They extracted (pulled out) this new element in 1898 and named it polonium, after Marie Curie's homeland of Poland. Although the polonium discovery was quite significant, the Curies were not satisfied. They could tell from their tests that another element, thousands of times more radioactive than uranium, existed in the pitchblende, but in such small amounts as to be nearly undetectable. Another French chemist confirmed the presence of this element—which the Curies had named radium—by examining pitchblende's spectral (wide band) lines. This did not convince many scientists, nor did it satisfy the Curies, who were determined to prove the existence of radium by extracting a measurable amount. This would be no small task, since several tons of pitchblende would have to be refined in order to produce even a gram of radium.

Pierre Curie abandoned his teaching position in order to assist his wife's research. Though Marie Curie was the engine and mastermind of the project, she and her husband worked as a team. In fact, all of the notes in her dissertation refer to the experimenters as "we"—neither she nor her husband are mentioned individually.

The Curies spent the bulk of their life savings to purchase waste ore from Czechoslovakian mines. They rented a leaky wooden shed in which they could refine the raw ore, and for the next four years they refined and purified the pitchblende, producing smaller and smaller samples that were more and more radioactive. The exhausting process, ordinarily performed by a team of several mine workers, took a physical toll upon the couple. This work, along with the birth of their daughter Irene, was nearly too much for the couple. Only Marie's intense determination kept things going. By 1902 the Curies had extracted one-tenth of a gram of radium, enough for Marie to finish her dissertation.

The Curies and Becquerel shared the 1903 Nobel Prize in physics for their contributions to the new science of radioactivity. Pierre Curie was also offered a professorial position in the Sorbonne's research laboratory, an offer that included his wife coming along as his lab superintendent. In 1906, however, tragedy struck when Pierre Curie was crushed to death in a traffic accident. Marie took over his position and continued his lectures at the exact point at which they were interrupted. She was the first woman to teach at the Sorbonne.

Working Alone

In the years after her husband's death, Curie conducted extensive work at the new Paris Institute of Radium. In spite of its mysterious properties, radium was used as a medicinal aid. Though it was often used without thought to its dangers or effectiveness, Curie proved that there were certain illnesses for which radium was effective. It played an important role in the treatment of cancer, and is still used for this purpose today. Curie also introduced the use of radium and X-ray technology in medicine. For the discovery of radium and polonium, Curie was awarded the 1911 Nobel Prize in chemistry, becoming the only person to hold two Nobel laureates in the sciences.

Except for World War I (1914-1918), during which she drove an ambulance, Curie spent the remainder of her life studying radium therapy. Though the process was successful, she received no royalties from its use, since she and her husband had chosen not to make money from their discovery by patenting (registering) it. Late in Curie's life, the dangerous nature of radioactivity took a personal toll. Curie's long years of exposure to radium resulted in leukemia (a disease that effects blood-forming organs), which lead to her death in 1934. Today, Curie is historically remembered as an outstanding female scientist, as well as one of the world's greatest researchers.