Hugo Bondy (1900–1985): an Austrian scientist of mass spectrometry in the twentieth century

Hugo Bondy (1900–1985), a fairly unknown Austrian scientist working in academia in the twentieth century made important contributions to the development of double-focusing sector field mass spectrometers. This article describes his life and scientific contributions in a fascinating biography meriting his achievements in the development and construction of new mass spectrometers. The article divides into three sections according to Bondy’s biography. In the first section, his education, career in academia, and research in mass spectrometry are displayed. The second section reconstructs his expulsion from the university, his persecution and resistance in the Nazi era, and his failed attempt to be reinstated at his position as a scientist. In the third and last section, Bondy’s career in the Austrian Federal Ministry of Education is depicted by focusing on his youth work, a controversy of his political affiliations, and his accomplishments and character in the civil service. Bondy’s life is taken as an example to uncover the process of exclusion in science with all its consequences. But also, the ethical aspects of science for education and the application of a scientific attitude to society are revealed by his actions.


Introduction
The Austrian contributions to the development of mass spectrometers are usually brought into context with known names such as Richard Herzog and Josef Mattauch. Nonetheless, in mass spectrometry-as in other fields of science as wellmany important contributions remain almost unknown. With his research, Hugo Bondy accomplished new insights towards the construction of mass spectrometers and to the field of isotopic analysis in the 1930s. However, he himself described his own career as complicated [1]. 1 Hereby, Bondy's biography 1 3 reflects and encapsulates the turbulent times of the mid-twentieth century in Austria for an academic. Three themes dominate and sum up his whole life: his passion for science and education, his attachment to Austria, and his ethics.
But why is Hugo Bondy's biography important for science? Foremost, his biography represents a researcher unrecognized by the scientific community, public, and history, even though, his contributions were essential to research in mass spectrometry and its later rise in use. Furthermore, Bondy's biography shows the exclusion of a person from science only based on discrimination. In addition, his treatment before and after World War II (WWII) by his faculty reveals the conduct, mechanisms, and effects of such policies of discrimination in a scientific community. All these aspects result in a unique biography that we present in this article.

Bondy's origin and family
Hugo Bondy was born as Hugo Heilig in Vienna on April 17, 1900 [2][3][4]. 2,3 His mother was Jeanette or Netty Heilig, 4 born as Huth; as his father Emanuel Heilig 5 was listed in the official records. Both were of Jewish faith [2,3,5]. The religious belief of the parents of Emanuel Heilig is unknown to the authors. From his mother's side, his grandparents were Sali Huth, born as Gartner, and Hermann Huth. Like her daughter, both grandparents were of Jewish faith [5]. Therefore, Bondy was considered after the later enacted Nazi laws for legal discrimination at least as a "Mischling ersten Grades", 6 more likely he was regarded as a "Jew" by the Nazi authorities.
On January 18, 1904, the court of the 8th district of Vienna ruled that the concluded marriage in Jewish faith between Emanuel and Netty Heilig was dissolved [5]. The reasons for the separation are unknown to the authors. However, Netty Heilig withdrew from Judaism, which the municipal office of the 9th district of Vienna officially recognized on January 10,1904. She was baptized in accordance with the Christian Roman Catholic tradition on January 12, 1905. For her new faith, she no longer used the former version of her first name ("Netty"), but instead used the name Anna [6]. Furthermore, she again used her birth surname, Huth, instead of the surname of her former husband, Heilig. On February 3, 1905, Anna Huth married Siegmund or Sigmund Alfred Bondy 7 in Vienna in accordance with the Roman Catholic faith. The marriage was officially approved on January 22, 1905 and announced in January/February 1905, after Emanuel Heilig publicly declared that he did not want to live with his converted wife anymore, which gave her the required consent from her former husband for remarriage [5].
Siegmund Bondy was an Austrian government employee [7][8][9]. His parents were Amalia Bondy, born as Kern, and Moriz Bondy; both were of Jewish faith [5]. The Nazi authorities considered him as a "Jew" [10], although Siegmund Bondy later stated that he was only "racially burdened" from his father side [11]. This would have meant that his mother converted to the Jewish faith. In the official records, Emanuel Heilig was erased as the father of Hugo Heilig, and Siegmund Bondy was listed as his father by the Jewish Community of Vienna (Israeltischen Kultusgemeinde Wien) [2]. A date for the conversion of Siegmund Bondy to the Roman Catholic faith is unknown to the authors. Likewise, no date or record of religious conversion or surname change from Hugo Heilig to Hugo Bondy was found by the authors.
Siegmund Bondy earned the title Regierungsrat for his years in government service [12] and worked in the rector's office of the Universität Wien [7]. In the year 1934, Siegmund Bondy was alleged to be a "Jew" and to have "'red' ties" to create a constituency for himself [13,14]. To these 2 Comments are placed at the footnotes to give further important information for historical research and more background regarding the used source material, events, and people. Dates and places of deaths and burials of mentioned people in the text were obtained, if not from the listed sources, from the online websearch Verstorbenensuche provided by Friedhöfe Wien (https:// www. fried hoefe wien. at/ verst orben ensuc he). 3 For the catalog of the study year 1922/1923 of the Montanistische Hochschule in Leoben a different date and place of birth is stated: May 14, 1900 in Mödling. Furthermore, the book of registration of the Montanistische Hochschule in Leoben state also 1901 as his birth year. 4 Jeanette, Netty, or Anna Heilig/Bondy (born Huth); date and place of birth: February 15, 1864 in Proßnitz (Prostějov), Moravia (Czech Republic); date and place of death: unknown to the authors; faith: Jewish/Roman Catholic; profession: unknown to the authors. 5 Emanuel Heilig; date and place of birth: May 4, 1864 in Proßnitz (Prostějov), Moravia (Czech Republic); date and place of death: unknown to the authors; faith: Jewish; profession: unknown to the authors. 6 Specific Germans words are, if possible, translated and listed by first mention with the original German word in brackets and italics. If no translation of the German word is possible, only the German word in italics is used throughout the text. An explanation of specific German words is given at the end of the text in a glossary with a translation and/or description of the term. 7 Siegmund or Sigmund Alfred Bondy; date and place of birth: December 10, 1870 in Ledetsch (Ledeč nad Sázavou), Bohemia (Czech Republic); date and place of death: unknown to the authors, buried on August 9, 1957 in Vienna, Austria (Cemetery of Neustift); faith: Roman Catholic; profession: civil servant. same inventory, the initials of the archive and the last identifier of the signature are stated after the first inventory reference. Footnote 1 (continued) anti-Semitic allegations, Siegmund Bondy replied that he had been a member of the Union of Christian Employees in Public Services (Gewerkschaft christlicher Angestellter in öffentlichen Diensten) and a cofounder as well as chairman of the Association of Civil Servants at the Universities (Hochschulbeamten-Verband) [15]. Politically, Siegmund Bondy can be linked to Austrian Christian conservatism due to two further passages. In his reply to the authorities of the university about the anti-Semitic allegations, he declared that the civil servants of the university welcomed the actions of the Austrian authoritarian dictatorship, which "cleaned up the surviving rubble" at the universities after its establishment [15]. In the later personal file of Hugo Bondy from the Austrian Federal Ministry of Education, part of a sentence in a draft letter was crossed out that claimed Siegmund Bondy was a supporter of the Viennese mayor, Karl Lueger [16]. At the turn of the century, Lueger was the leader of the conservative Christian Social Party (Christlichsoziale Partei) in Vienna and used anti-Semitism for political agitation, which made him an idol for Adolf Hitler [17]. 8 However, Siegmund and Hugo Bondy suffered from anti-Semitic and racial discrimination from 1938 to 1945 [18][19][20]. Nevertheless, the religious belief of both of them was always stated as Roman Catholic in the records after Hugo Bondy's birth and since Siegmund Bondy's marriage. Their religious belief was then never listed as Jewish.
Bondy was the oldest son of three children in the family of Siegmund and Anna Bondy. His two siblings were his sister Marie Bondy and his younger brother Friedrich or Fritz Bondy [10,[21][22][23]. Friedrich Bondy was an employee in the faculty of law of the Universität Wien. Like his brother, Friedrich Bondy was also discharged from the university in 1938 due to anti-Semitic and racial discrimination as a result of his decent [24,25].

Becoming a scientist
Hugo Bondy acquired his formal education at the school Nieder-Österreichisches Landes-Realgymnasium in Mödling [4,7], which allowed him to obtain the high school diploma (Matura) on July 2, 1919, and entitled him to study [26]. The school focused more on natural science than on humanities and specifically used a practice-orientated curriculum in physics and chemistry for the education of the students [27]. Perhaps because of this education, he either attracted a primary interest in natural science or his abilities in this field were cultivated. This was certainly a benefit for his later studies at the universities.
In 1918, Hugo Bondy joined a one-year volunteer mili- 1 3 amber and pressed amber (Ambroid) under the influence of radium β-rays [40,41]. The evaluation report of his thesis from March 21, 1931, was in favor of his graduation [41]. Bondy then presented his thesis on March 23, 1931 [26,38]. He first had a two-hour exam in front of a commission on March 26, 1931. Members of the commission were: Prof. Stefan Meyer, Prof. Egon Schweidler, and Prof. Hans Hahn. Bondy succeeded the exam with distinction. On April 25, 1931, Bondy also passed a second exam of one hour. To this exam, Prof. Heinrich Gomperz and Prof. Robert Reininger were assigned [26]. Eventually, the title of philosophical doctor in physics with mathematics [31,42] was granted to Hugo Bondy on May 15, 1931 [26], and his career at the university and in science gained momentum.

A career in academia
Bondy's work-related engagement with the Universität Wien started in October or November 1929 first as wissenschaftliche Hilfskraft and later as Hilfsassistent at the 1st Physical Institute [7,35,36,43]. On June 1, 1931, Hugo Bondy began as außer-ordentlicher Assistent at this institute with an official contract until May 31, 1933 [44-48]. This contract was renewed for two more years on March 11, 1933 [49]. However, the contract was promptly revoked in May 1933 and a new contract was only offered until the end of May 1934 [50]. Two possible reasons, known to the authors, might have triggered the cancellation of Bondy's old contract and the offer of a new but more limited contract. The first reason was of a political nature. With the resignation of the three speakers of parliament (Nationalratspräsidenten) due to a vote on March 4, 1933, and the prevention of the reconstitution of the parliament of the First Republic of Austria by its Federal Chancellor, Engelbert Dollfuß, on March 15, 1933, an authoritarian dictatorship, also known as Austrofaschismus or Autoritärer Ständestaat, was established [51]. To balance the state budget, the government cut spending to the institutes of the universities and aimed for their reduction in number and size [52,53]. Likely as a result of this, Bondy's contract was re-evaluated and terminated by the authorities [50,54].
The other reason was presumably related to a later change in the faculty. In 1934, Prof. Gustav Jäger-head of the 2nd Physical Institute (II. Physikalisches Institut) [48]-retired [55]. Prof. Egon Schweidler [56]-Bondy's doctoral examiner and head of the 1st Physical Institute-followed as his temporary successor. Probably in anticipation of this retirement, Bondy's contract was canceled as well, and his new contract was limited to conclude in 1934 due to uncertainty in planning and financial matters [52,53]. In addition, Bondy was also the latest außer-ordentlicher Assistent at the 1st Physical Institute.
Other probable reasons are unknown to the authors. The new contract stated only his prior position without a salary as unbesoldeter außer-ordentlicher Assistent. The old position with salary at the 1st Physical Institute was terminated [50]. Bondy accepted the position as an unbesoldeter außerordentlicher Assistent with a research grant (Forschungsstipendium) and worked until 1934 [36,57].
As a work requirement, he had to swear allegiance to the new regime and its authorities in the state and university in the form of a code of obligation (Pflichtenangelobung) on June 26, 1933. Bondy had to pledge that he does "not belong or will not belong in the future to a foreign political organization" [58]. Nonetheless, Bondy never became a member of any political party before 1945 [59].
On February 24, 1934, Hugo Bondy's contract as an unbesoldeter außer-ordentlicher Assistent with research grant was extended until May 31, 1936 [36, 56, 60-62]. Bondy was then officially promoted to Assistent III. Klasse during this contract on October 11, 1935 [56, 62]. In this time period, changes in the organization of the faculty influenced Bondy's later career. The 1st Physical Institute and the 2nd Physical Institute, both under the leadership of Prof. Egon Schweidler, were officially united to one institute, the United 1st and 2nd Physical Institute (Vereinigtes I. und II. Physikalisches Institut). This was the result of the policy of the government to reduce the number of institutes at universities [52,53]. At this newly formed institute, Hugo Bondy received a new position on December 14, 1935 as an Assistent III. Klasse, this time with salary [62]. However, his appointment by Prof. Schweidler sparked some resistance, specifically by the scientific staff of the 2nd Physical Institute. Due to general spending cuts, a fight over resources was caused between the institutes, which reached its peak by the unification of the 1st and 2nd Physical Institute [52,53] 10,11 The argument regarding low working abilities as the only reason for Haschek's resistance against the nomination of Bondy to the position can be doubted for several reasons, but first, Prof. Haschek's statement has to be put in context of its time. After WWII, the infrastructure was mostly destroyed in Austria (and at the Universität Wien), the land was occupied by the Allied forces and government spending was limited. Therefore, Prof. Haschek-as only the temporary director of the 2nd Physical Institute immediately after the war-further argued that to provide a job and financial support from the university for another person like Bondy was inappropriate-however, rightful the claim for reinstatement was [63,64].
One reason that contests Prof. Eduard Haschek's claim of Bondy's moderate working skills is that Bondy later received a work extension, as well as an even higher Assistenten position, presumably for his time of service or as a promotion for his good work [65]. Another reason can be internal disputes of the unification of the two institutes under the leadership of Prof. Egon Schweidler. The nomination of Prof. Schweidler as final head of the unified institute could be interpreted by the three men as an unrightful takeover, in which the position of director should have belonged to one of them. In consequence, any action from him would have been opposed as a sign of disobedience and Bondy-as a member of Prof. Schweidler's institute-could have been viewed as "his men". After Prof. Schweidler's retirement in 1939 as head of the United 1st and 2nd Physical Institute [66,67], the institutes were split again and two men out of the three dissenters advanced their careers during WWII. Georg Stetter became the head of the 2nd Physical Institute in 1939, meanwhile Gerhard Kirsch became the director of the 1st Physical Institute in 1941 [53]. Prof. Eduard Haschek remained on his post at the 2nd Physical Institute, but was banned from entering the institute during the Nazi era [68,69]. A third reason might have been politically and racially motivated. Although there is no indication that Bondy's lineage was an issue before and in 1935 or known to his colleagues, two men were leaning to the Nazi ideology. Gerhard Kirsch was openly national socialist minded and was a member of the National Socialist German Workers' Party-Nazi Party (Nationalsozialistische Deutsche Arbeiterpartei-NSDAP). Georg Stetter was a convinced national socialist and NSDAP member as well [53,70,71]. A final reason was maybe a personal one. However, it has to be doubted that Bondy's working skills alone, if they were in reality sufficient or insufficient, were the only reason for the opposition towards him at that time and later after WWII. In any way, the real and complete motivation for the opposition against Bondy cannot be reconstructed.
Eventually, Bondy had a contract as Assistent III. Klasse from June 1, 1936 until May 31, 1938, which he fulfilled until his expulsion [62, [72][73][74]. On January 10, 1938, he was officially promoted to Assistent II. Klasse [65,75,76]. Furthermore, an extension of the contract was given to Bondy for the same position (from June 1, 1938until May 31, 1940 on January 29, 1938 [76]. Prof. Egon Schweidler justified Bondy's extension by referring to his very good work as an administrator of the institute archive and material depot as well as to his proven excellence in assistance to a lectureship of Prof. Karl Przibram [77]-Assistent at the Institute for Radium Research [78]. Therefore, Prof. Schweidler considered Bondy as irreplaceable for these duties [77]. In addition to his job at the university, he passed the teaching exam (Lehramtsprüfung) on February 4, 1935, which allowed Bondy to teach mathematics and physics on a high school level [28]. From 1935 to 1936, he worked as a teacher for his one-year probation in the state high school (Staatsgymnasium) of the 8th district of Vienna [31]. However, Hugo Bondy reached the peak of his academic career at the beginning of March 1938.

Research in mass spectrometry
Major achievements in mass spectrometry were laid in the years around Bondy's birth. However, cathode rays (Kathodenstrahlen-electrons) and canal rays (Kanalstrahlenpositively charged ions) were already discovered in the nineteenth century [79,80]. Joseph John Thomson demonstrated that cathode rays consist of electrons and accomplished their deflection by electric or magnetic fields in 1897 [79][80][81].
One year later, Wilhelm Wien proved that the canal rays were positively charged particles and could be deflected by a strong electric or magnetic field [79,80,82]. As consequence of these discoveries, Thomson and his scholar Francis William Aston built the first mass spectrometer in 1912 [79,80,83,84]. Charged particles could be deflected and separated according to their kinetic energy and mass to charge ratio. As a result, elements, isotopes, and later chemical compounds, were distinguishable by mass spectrometry. 10 In case of direct quotations in German, the cited text was translated into English and the original text was placed into a footnote. The corresponding author takes full responsibility for any transcription and translation errors. 11  Meanwhile, Frederick Soddy discovered that the element lead had two different masses depending on the origin of its radioactive decay. Soddy called the phenomena of atoms from one element, which have the same chemical qualities, with different masses "isotopes" in 1913, after a suggestion of his friend Margaret Todd [79,80,85]. Contributions from scientists of universities of the Austrian-Hungarian Empire, namely: Friedrich Paneth, George de Hevesy, Otto Hönigschmid, and Stefanie Horovitz, influenced Soddy's work and conclusions regarding isotopes [86]. During the time of the implementation of the term isotope in science, Thomson and Aston found two isotopes for neon with their mass spectrometers [79,80,87]. The existence of isotopes was later confirmed through the discovery of the neutron by James Chadwick in 1932 [79,80,88].
The invention of mass spectrometry established a new scientific area in natural sciences allowing for qualitative and quantitative determination of elements, isotopes, isotope ratios, and chemical compounds from small molecules to large proteins. Due to mass spectrometry, isotopes of elements were continuously discovered and isotope ratios more precisely determined, foremost by the leading work of Aston, in the first half of the twentieth century. Furthermore, the field of mass spectrometry gained significant interest in nuclear research-especially during WWII. After a research grant in the USA, Josef Mattauch-a former Assistent at the 3rd Physical Institute (III. Physikalisches Institut) of Prof. Felix Ehrenhaft-returned to the Universität Wien and positioned his research in the field of mass spectrometry in the late 1920s. Here, he specialized on the theory and construction of mass spectrometers. Under his leadership, and later by his two scholars, Richard Herzog and Alfred Bönisch, mass spectrometry was established and continued as a research area at the Universität Wien [53]. In 1929, Hugo Bondy joined the 1st Physical Institute [7,36], where Josef Mattauch was außer-ordentlicher Assistent [89], and probably came in contact with mass spectrometry for the first time.
After his dissertation in 1931, Bondy published his first paper in 1933 [90]. In this article, he and his co-author Karl Popper 12 [91][92][93] constructed a mass spectrometer for velocity and direction focusing [90]. Due to the preference of mathematics and physics as his study subject, he fit the profile and was qualified for such a task. Furthermore, Bondy and Popper had the blessing and support from Prof. Egon Schweidler. Josef Mattauch was specifically thanked for his initiation of the paper, suggestions, and support [90].
Therefore, it seems that Bondy had a good relationship to his superiors and collaborated with Mattauch in the field of mass spectrometry. Bondy also acknowledged a doctoral candidate, Franz Schendl, 13 for his help during the measurements [90,[94][95][96].
For their mass spectrometer, Bondy and Popper orientated their construction under the considerations of a paper from Walter Bartky and Arthur Jeffrey Dempster [97], in which the path of charged particles under the simultaneous combination of a radial electric field and a homogenous transversal magnetic field is discussed. This combination has the advantage of focusing charged particles in direction and velocity (double focus), which brings a higher precision to the mass to charge measurements [90,97]. Bondy's and Popper's realization of the theory (see Fig. 1) was a flat circular box made of brass, with an inner diameter of 90 mm and a height of 16.2 mm, as the measurement chamber. For the covers of the box, soft iron with a diameter of 120 mm was used to fit in the pole pieces of an external electromagnet. The one cover (here top) was only loosely closed for easy access, whereas the other cover (here bottom) was soldered to the brass. In the box, a cylindrical capacitator with a center angle of 127° 17' (127.3°) [98] was fixed and oriented around the middle point with hard rubber for insulation. Two slits with changeable widths were insulated and mounted at the beginning and end of the capacitator. The ion source was a small platinum strip (10 × 4 × 0.01 mm) with vertically tapered holes-on which glass as a sample was meltedheld by copper rods insulated with quartz, going through the brass, and fixed outside. A small brass cup fixed on a highly-insulated brass rod going through the brass of the box and connected to an electrometer functioned as a detector. The last detail was the flange connection to a vacuum system that produced a high vacuum for the measurements of ca. 1 × 10 -6 mm Hg (ca. 1.3 × 10 -4 Pa) after ca. 12 h. To establish the high vacuum, all metal parts and joints were covered and sealed with a special varnish [90].
The accomplishment of the paper was the successful operation of the built apparatus and the proof of the principle and method. Ions were emitted from the glass through a heating current forming the glowing anode and then accelerated to the entrance slit to a certain velocity. In the capacitator, the radial electric field deflected the ions to the outside, while the homogenous transversal magnetic field deflected the ions to the inside of the box. The detection was achieved after the exit slit with a brass cup. By holding the acceleration voltage (potential difference) and the electric field constant, different masses could be separated by varying the magnetic field [90]. An improvement compared to the measurements with only a magnetic field [99] was reached through the combination with an electric field, as it was shown by sodium ( 23 Na) [90]. The beam of sodium ions with a magnetic and electric field was by 30% narrower than without the electric field. Therefore, a focus in direction and velocity (double-focusing) of the ions was accomplished. The 23 Na and 39 K beams reached their maximum intensities in the experiments at values of the magnetic field strength quite close to the theoretical calculations [90]. Differently to Dempster's mass spectrometer from 1918 [99], the magnetic field was changed, not the potential difference (acceleration voltage), because of the experimental design to prove the focusing effect of the electric field [90]. Compared to Dempster's mass spectrometer with a magnetic field of 180° and only focus in direction [90,99], Bondy's and Popper's mass spectrometer had a field of only 127° 17′ and could be higher in resolution because of focusing in the direction and velocity of the ions [90]. Furthermore, other important practical information was mentioned. A scan of low mass ions up to the masses of potassium was possible due to varying the magnetic field. During the measurements, the vacuum pumps could run constantly to remove created particles and invading atmosphere to reduce the scattering of the beam. The heating current had to be held constant and as low as possible to have good reproducible results over a longer measurement time. Another mentioned effect was that with increasing distance between the ion source and the entrance slit, the resolution decreased. In some measurements of sodium and potassium with a larger slit width, double or two maxima appeared for each isotope mass. The two authors assigned this effect to the geometry of the instrument in regard to its arrangement of anode, slit, and capacitor [90,97,100].
The paper from Bondy and Popper was received by the journal Annalen der Physik on April 16, 1933 [90]. Shortly before, on March 16, 1933, Prof. Egon Schweidler presented their findings in a meeting of the Mathematic-Natural Scientific Class of the Academy of Sciences in Vienna (mathematisch-naturwissenschaftliche Klasse der Akademie der Wissenschaften in Wien) along with a published abstract [100]. In both cases, it was stated that their findings benefit the construction of an improved instrument [90,100]. Nonetheless, in 1934, Josef Mattauch and Richard Herzog published a paper [101] about theoretical considerations for a new geometry of mass spectrometers, which is still in use today. They proposed an arrangement in which the radial electric and the homogenous magnetic field were positioned one after another to achieve the double-focusing effect of direction and velocity. In this paper, Bondy and Popper are credited for the first instrument that realized the doublefocusing effect for ion beams [101,102]. If and how much Bondy's and Popper's work in potential exchanges and discussions contributed to Mattauch's and Herzog's theoretical considerations remains unclear, but there was no further acknowledgement of their achievements. However, Josef Mattauch mentioned Bondy's and Popper's work and printed a picture of the measurement chamber of their mass spectrometer already in an article of 1932 [103]. Albert Edward Shaw credited Bondy and Popper as well for their realization of Bartky's and Dempster's theoretical considerations when he investigated the influence of crossed magnetic and electric fields on electrons [104]. Later, Alfred Otto Nier declared that presumably the first serious attempt to measure precise atomic masses with double-focusing mass spectrometers was realized by him and his colleagues, but admitted that Bondy and Popper were the first pioneers in building a functioning instrument using the double-focusing effect. Nier pointed out that Bondy's and Popper's double-focusing instrument did not achieve the same performance in resolution as the single-focusing mass spectrometers of that time period [105]. Diaz [93] mass spectrometer could reach a resolving power of 380 at 23 Na + [98].
Bondy's next known scientific contribution was a talk in a meeting-chaired by Prof. Karl Przibram-of the Gau Association Vienna of the German Physical Society (Gauverein Wien der Deutschen Physikalischen Gesellschaft) on May 13, 1935, and was published as a short abstract [106]. In his talk, he presented the advantages of a double-focusing mass spectrometer for energy consumption and mass resolution, the description of such an arranged instrument, and results of isotope ratio measurements from 39 K/ 41 K and 85 Rb/ 87 Rb [106]. The findings were published in Bondy's second paper [107] with Karl Popper and Gerhard Johannsen 14 [108][109][110] as co-authors. It was received by Zeitschrift für Physik on April 3, 1935. The authors thanked again Josef Mattauch for his suggestions to their work and Franz Schendl for his assistance [107].
Compared to Bondy's and Popper's first version of the mass spectrometer, several adjustments and improvements in the construction changed the capabilities of the second model of the instrument (see Fig. 2). The housing was arranged as a tube around the cylindrical capacitator to reduce the room for the necessary evacuation. To obtain a higher vacuum, two parallel, oval orifices with a larger diameter were established for the connections to the vacuum pumps. Both ends of the tube were sealed with brass plugs. The ion source with the entrance slit was mounted on the plug at the one end, and the exit slit with the cup was attached on the plug on the other end. The width of these two slits close to the ends of the capacitator was adjustable. The cylindrical capacitator was mounted on two glass bridges for insulation. The authors also described disadvantages and errors that the design of their mass spectrometer produced through the external magnetic field on the ion source and acceleration field area, and through alteration of the electrical potentials in the cylindrical capacitator and cup. Nevertheless, they stated there was no negative effect on measurements of the relative isotope abundances [107].
For the paper, Bondy and his two co-authors measured the isotope ratios of 39 K/ 41 K, 85 Rb/ 87 Rb, and strontium. The potassium samples were two different types of glasses, one was Pyrex® glass with or without substitution of rubidium hydrogen carbonate (RbHCO 3 ) or strontium dihydroxide (Sr(OH) 2 ) and the other was a fusion of silicon dioxide (SiO 2 ), potassium hydroxide (KOH), and Sr(OH) 2 . The results of the isotope ratios were quite close to the state of the art obtained values of today, although the precision is not comparable to modern instruments. For potassium isotopes, the three authors obtained a value of 39 K/ 41 K = 16.2 ± 2.2 (n = 13) for the two types of glasses and with or without the two substituents to the Pyrex® glass [106,107]. The actual representative ratio of terrestrial isotope abundances is 39 K/ 41 K = 13.856661 [111,112], which was still an improvement to the known value of approximately 39 K/ 41 K = 18 at the time [107]. In the case of rubidium, Bondy and his two co-authors measured a value of 85 Rb/ 87 Rb = 2.68 (n = 3) for a fusion of Pyrex® glass with RbHCO 3 [106,107]. 85 Rb/ 87 Rb = 2.5932 is currently the representative ratio of terrestrial isotope abundances [112,113] and the authors measurements were closer than the prior value of 85 Rb/ 87 Rb = 3.0 [107]. To test the instrument for the discovery of possible new isotopes, strontium was investigated. The results with two fusions of SiO 2 , Sr(OH) 2 , and either sodium hydroxide (NaOH) or KOH for strontium isotope analysis were inconclusive because the two found maxima were apart by two mass units and the maxima with the lighter mass was two to three times stronger than that of the heavier mass. All three authors suspected, on the basis of  [110] theoretical calculations with the international atomic weight of strontium of the time and on the observed premises, an isotope ratio of 87 Sr/ 89 Sr = 1.78 during that time. However, their obtained data showed an isotope ratio of 2.58 (n = 5). Because of the deviation to the theoretical calculated value, the hypothesis of an isotope ratio with 87 and 89 strontium was abandoned. The observations were later linked by the authors to a possible impurity through contamination with rubidium during the sample preparation. The hypothesis of an 87 Sr to 89 Sr isotope ratio was not far-fetched, because of Josef Mattauch's isotopic systematic in 1934, two other isotopes of strontium were suspected ( 84 Sr and 90 Sr) [107]. Today there are no stable 89 Sr or 90 Sr confirmed in their existence. Nonetheless, at the end of the abstract from his talk, Bondy wrote the following prophetic words regarding the potential of his advanced instrument: It is finally the expectation that, with the described apparatus, results from further measurements of the relative isotope abundances of other elements can be communicated in the foreseeable future." [106] 15 Although Bondy only referred to the newly built second version of the mass spectrometer, constructed by him and his colleagues, in another sense he was right that doublefocusing instruments, in general, would gather new and more information about the isotope abundance of the elements in the future. However, Mark Gordon Inghram highlighted in a later book contribution that Bondy's, Johannsen's, and Popper's instrument had the disadvantage of using a large magnet, indicating its application was not easy in practice, a limiting factor for its general use at the time. Nevertheless, he listed their mass spectrometer as the first double-focusing instrument in scientific literature, but cited 1934 as the year of publication [114]. In 1942, Bond's, Johannsen's, and Popper's mass spectrometer was mentioned in the context of cross field spectrometers [115]. For Bondy, the second paper symbolized a transformation in his research, he went from the construction of mass spectrometers to the investigation of isotope ratios; a new door of interest was opened.
Hugo Bondy set another focus of research related to ion emission of the alkali metals in glass. In a meeting of the Mathematic-Natural Scientific Class of the Academy of Sciences in Vienna on April 23, 1936, Prof. Egon Schweidler presented a work from Hugo Bondy and Viktor Vanicek 16 [116][117][118][119], which was published as an abstract [120]. The findings were published in the journal Zeitschrift für Physik. The manuscript was received by the journal on April 27, 1936. In the acknowledgement, Prof. Egon Schweidler and Josef Mattauch were again thanked for their support and suggestions [121].
In the paper, Bondy and Vanicek performed their isotopic measurements with the improved second model of the mass spectrometer on different types of glass. Herein, they documented two relationships of their observations in regards to ion emission. First, they observed a correlation between the heating temperature and the ionization of the alkali metals in glass. At the beginning with low heating temperatures, potassium was ionized first, followed by sodium and then lithium with increasing heating temperatures. Both authors concluded that a direct link between ionization voltage and heating temperatures exists, which corresponds to the ionization energies and principles in mass spectrometry today. Ions from elements with a low ionization energy are created before ions from elements with a high ionization energy. Second, Bondy and Vanicek monitored that over time the ion emission of elements with high ionization potential decreased in the emitting surface of the glass. Therefore, with longer measurement time, more ionized elements with a low ionization potential are found in the ion beam. As a result, the concentration of high ionization potential elements in the surface declines [120,121].
For the measurements of relative isotope abundances, Bondy and Vanicek investigated the isotope ratios of lithium, potassium, and rubidium in glass. The isotope ratio of 7 Li/ 6 Li was stated by them as approximately 7 Li/ 6 Li = 12, which was in line with most of the measured values during that time [120,121]. 7 Li/ 6 Li ranges from 11.821 to 51.632 [112,122] and represents the terrestrial range of the isotopic composition. Compared to the previous paper and the state of the art 39 K/ 41 K isotope value in nature, the authors improved their results to a mean with 39 K/ 41 K = 14.1 ± 0.1 (n = 15 or n = 9) and a higher precision [120,121]. In the same matter, the measured isotope value of 85 Rb/ 87 Rb was improved to a mean of 85 Rb/ 87 Rb = 2.57, which is closer to the actual value for terrestrial Rb known today [121]. Nevertheless, both discussed also the appearance of double or two maxima of isotope masses in their measurements and accounted two phenomena for that resulting into two different groups. The first type of these maxima occurred by reaching a too large distance between the ion source and the capacitator because the external magnetic field had then a stronger impact on the trajectories of the ions. According to the authors, the double maxima disappeared by simply adjusting the ion source, slits, and capacitator. For the second type of these double or two maxima, it was suspected that a high and too fast acceleration of the heating temperature was causing the effect. No geometric adjustment could avoid these maxima and the recommendation from Bondy and Vanicek was to accelerate the heating temperature slowly and not to a too high temperature. However, the isotope ratios could still be measured. Only the mechanism of the reduction of the elements with a high ionization potential on the emitting surface of the glass was still unclear to them and open for speculation [120,121].
After the publication of his third paper, Bondy continued his work at the university. He probably supervised two more students that worked on their dissertations with the improved second version of the mass spectrometer. The two doctoral students were Irmgard Lehmann 17 [123][124][125], presumably the first Austrian woman working in the field of mass spectrometry, and Anton . Both worked on further improvements of the instrument and investigated Li isotopes. The two graduated after March 1938 [124, 127]. A possible subsequent collaboration and publication of the conducted work with Bondy was interrupted due to the upcoming political events.

Expulsion from the university
The situation for Hugo Bondy changed dramatically with March 12, 1938. German troops crossed the border and occupied Austria. Through the so-called "Anschluss", Austria became a part of the Third Reich. Because of different laws in place between Austria and the Third Reich, a transition period of legal constitution occurred after the annexation in the former Austrian territory, now called "Ostmark", to establish the German rule under the pretext of legality. On a daily basis and step by step, laws and decrees were enacted after the model in Germany. Bondy would be affected by that very soon.
Already on March 13, 1938, a law for the unification of Austria and Germany (Gesetz über die Wiedervereinigung Österreichs mit dem Deutschen Reich) was proclaimed, which would function as the basis of all further legal actions [132]. On May 17, 1938, the still formally called Austrian Ministry of Education released an edict to dismiss persons from the universities [129,130]. Bondy obtained a formal notice of his dismissal on May 23, 1938, from the new acting dean of the faculty of philosophy, Viktor Christian -member of the NSDAP and later SS (Schutzstaffel) [130,131]: On May 31, 1938, a decree for reorganization of the Austrian civil service (Verordnung zur Neuordnung des österreichischen Berufsbeamtentums) was announced [132]. This decree was based on the German counterpart laws Gesetz zur Wiederherstellung des Berufsbeamtentums of 1933, to eliminate all unfavorable civil servants, and Reichsbürgergesetz of 1935, one of the so-called "Nuremberg Laws" ("Nürnberger Gesetze") for legal anti-Semitic and racial discrimination. Bondy stated that the definition of its §3 applied to him [129], which says in (1): "Jewish officials, officials who are Jewish Mischlinge, and officials who are married to a female Jew (a male Jew) or to a Mischling ersten Grades, have to retire. They receive Ruhegenuß (indemnity) in accordance with the regulations in force for retirement due to incapacitation; they then only receive a continuous Ruhegenuß, if they have an allowable time of service for the Ruhegenußbemessung with a minimum of 10 years." [132] 20 In an appeal of reparation to the City School Board of Vienna (Stadtschulrat von Wien)  Although there is no detailed personal report from him about his persecution, the account of his relatives can give some insights of the situation he faced during the Nazi reign. Siegmund Bondy, was now married to his second wife, Rosa Bondy, born Kornher or Kornherr. She was Roman Catholic, had no Jewish heritage, and was considered by the Nazi ideology as an "Aryan". In a statement to the Nazi authorities during the persecution, she wrote that she originated from a "national socialistic family". Her older brother, Franz Kornher, was a member of the SA (Sturmabteilung), and her younger brother, Karl Kornher, was a member of the SS and claimed to be involved in the national socialist coup against the Austrian authoritarian dictatorship in 1934 [10,[133][134][135]. However, due to the Nazi occupation, Siegmund Bondy's money and property came under government supervision. Therefore, Siegmund Bondy needed to transfer his assets to his second wife and her family [136]. Nevertheless, it did not ease the pressure of the Nazi regime on him. Presumably, neither did his pleas to the Nazi authorities that he helped NSDAP members of the Universität Wien during their time of persecution by the Austrian conservative regime [10,134]. Even stating that the father of Arthur Seyß-Inquardt was Siegmund Bondy's teacher in high school (and personally known to him) likely did nothing to create an impression on the Nazi authorities [134]. The Nazi Party of Vienna actually recognized Siegmund Bondy as unpleasant at the Universität Wien [137]. For Hugo Bondy's siblings, Fritz and Marie Bondy, the only way to escape the persecution was emigration. Both emigrated abroad, the exact destination of their migration is unknown to the authors. Siegmund Bondy had to afford all the required legal fees and expenses by himself so that these two children from his first marriage could leave the Third Reich [10]. In 1948, Siegmund Bondy summarized the time of the persecution as follows: "I had now to endure all the known torments from the NS [national socialists], relocation, house searches, bloody abuse in the Gestapo, and loss of my longtime savings. Subsequently, even my pension was cut to such a bare minimum that three people (myself, my wife, and her mother) could not live from it. I carved out my life from the proceeds of teaching 'Mischlinge', I owe most of them to the recommendation of the Catholic Action from the Archdiocese of Vienna." [11] 22 This statement of Siegmund Bondy gives a glimpse of what Hugo Bondy had to endure in the coming years under Nazi rule since he stayed in Austria.
On June 1, 1938, the decree that expelled Bondy from the university was enacted. He was not the only person affected by the new authorities and their policies. The professors Stefan Meyer [70,138,139], Felix Ehrenhaft [53,139], and Karl Przibram [70,139,140] were also expelled from their positions due to the anti-Semitic and racial discrimination [70,139,141]. In total 32% of professors and lecturers in physics were dismissed at the faculty of philosophy, and 54% of the university teaching personnel from all faculties of the Universität Wien were released due to their undesirability by the new regime [70,141] (see Fig. 3). Meanwhile Josef Mattauch [142], Richard Herzog, Georg Stetter, and Gerhard Kirsch were able to pursue their careers [53,70]. However, Hugo Bondy would never return to his scientific career in mass spectrometry. 21

Education as resistance
Unlike some of his expelled colleagues, Bondy never left Austria and did not emigrate to another country to continue his scientific career elsewhere. The reason for this remains unknown. However, Bondy did not speak any foreign language, which did not facilitate the option of migration [143].
From October 4, 1938 to November 30, 1940, he worked as a regular school teacher in the service of the City of Vienna. Later, Bondy was a teacher and director of a private primary and secondary school for children considered as "non-Aryan" ("nicht-arisch") in the Grüngasse 14 of the 5th district of Vienna from December 1, 1940 to August 15, 1942. Afterwards, he was an educator and director of a private children's home for Jewish children in the Mohapelgasse 3 of the 2nd district of Vienna until April 1945 [28,31,[144][145][146].
In the files of the Austrian Federal Ministry of Education, only a small comment exists dealing with this period of his life. There, the following is stated: "[… Bondy devoted himself], with no regard for his own person, to the care of Jewish orphans in Vienna, until they, too, were forcibly removed from his custody and, for the most part, taken to extermination camps. [...]" [28] 23 Other files in the archives regarding his time as caregiver do not exist (anymore) to the authors' knowledge. Only his courage to take care of the children during the air bombardments of Vienna was documented [144]. However, Bondy wrote a direct account of his time as a caregiver in a newspaper article in the year 1947 [147]. The article has to be considered in the context of WWII and the post-war period to understand Bondy's motives. Provoked by the question, how many Austrians really actively resisted against the Nazi regime, Bondy felt it was his obligation to point out his time of prosecution. In his opinion, many who did resist were either dead or did not want to be worshiped as heroes. His motivation was on the one hand personal, to honor the people that served with him during this time and by telling their story as a group. It was on the other hand, political, to show his fellow citizens and the rest of the world that not all Austrians were complicit with the Nazi regime [147].
Bondy was aligned to a new idea of Austria and what it should represent. Therefore, a certain narrative was depicted in his article. In that perspective, the demarcation between Germans and Austrians and the responsibility for the atrocities of the war was emphasized. As a result, the general view of an Austrian national resistance against an occupation by force, which also played into the role of Austria as a first victim of the Third Reich aggressions and the creation of distance to the responsibilities from the war for Austrians, was fostered. The narrative was that not many, but few, Austrians welcomed and many, not few, Austrians opposed the Nazi regime. Furthermore, this narrative should support the intention of the recreation of Austria on the map by the allied forces, which occupied the country at the time. For Bondy, the idea of a new Austria was tempting as a vision to overcome the past with its atrocities and to build a better and more just world for future generations [147].
Because of his personal history, Bondy's account is composed on the emphasis of Austria as an alternative way to the Nazi ideology for resistance and national identity. In light of this, Bondy considered his dedication to engage in the education of "non-Aryan children" ("nicht-arischen Kindern") as a form of Austrian resistance [147]. He described it as follows: "While in 1938 all Austrian schools were transformed into 'German' schools with a curricula from Berlin; while in all schools of our country from the lectern [speaker's desk] only Nazi ideas had to be lectured and often were lectured; while the children and young people were systematically intellectually crippled and emotionally uprooted; until the final days of Hitler's Nazi Germany in Vienna, a small group of children existed, although shrinking year by year (first some thousands, then some hundreds, subsequently only approximately 80), that had the misfortune to live in Nazi Germany as so-called 'non-Aryan' children, but had the fortune never to be taught the Nazi-but only the old Austrian-curricula and to be educated following human principles. It is improbable sounding and yet the pure truth that, in Vienna from 1938 to 1945, a pure Austrian school existed with an Austrian curriculum and Austrian teachers, with 'Guten Morgen' and 'Grüß Gott' instead of 'Heil Hitler', without war collections, without war training and HJ [Hitlerjugend-Nazi male youth organization], and without KdF [Kraft durch Freude-Nazi leisure organization], but instead with diligent learning and a lot of worries and tribulations; with tears and saying goodbye again and again, when again some met the fate of deportation." [147] 24 At the end of the article, Bondy reflected on this time as a form of resistance and as a part of a larger national effort to the mission of restoring Austria [147]. He classified the period in the following way: 23  "Thus we [the teachers and pupils] were a separate and unique partisan group; although our 'heroic deeds' cannot be compared to those fighters with weapons, we nevertheless belong to the 'unknown Austrians' who never lifted a finger for Hitler, but fought against him in word and deed under constant and years-long danger to our lives for a better Austrian future. May arguments like these also be heard in the dispute about Austria's participation in the resistance!" [147] 25 However, Bondy also reported about the establishment and work regarding the private school for the "non-Aryan children", and the satisfaction he obtained from their education [147]. He wrote: "Until 1940, Gemeindeschulen had existed for these ['non-Aryan'] children, then they were resolved as redundant-for Theresienstadt and Auschwitz, a true redundant preliminary stage. But other opinionsthank God-disagreed with that. In the summer of 1940, I received the order […] to establish a school for this ['non-Aryan'] children that were excluded from the public schools. Among my fated companions, I found employees and created and directed the desired school. It became an eight-level school Volks-und Hauptschule and I can say with joy: All children from this institution, as far as they were not murdered, are by no means behind their 'Aryan' peers in terms of knowledge and are, in courage, dignity, and wisdom of life, far superior than them, of which I can convince myself repeatedly." [147] 26 But the situation worsened dramatically during the war period with the mass deportations into concentration and extermination camps in the German occupied countries of Central and East Europe [144]. Bondy had to face the continuous decline of the number of fosterlings and colleagues, but also the constant fear from the authorities that dominated everyday life, which he described as follows [147]: "Year by year we were fewer: teachers and students. As the 'teaching staff' only consisted of three people, we divided the children into three groups by age and every one of us was a teacher for all subjects. We gave ourselves a real curriculum, which had to be rearranged monthly, and tried to keep a tight schedule. A lookout service was part of our schedule, one for the American bombers (which we considered as friends, but still feared) and another for our mortal enemies, the SS [Schutzstaffel] and SA [Sturmabteilung], the Gestapo [Geheime Staatspolizei], or other Nazi-henchmen." [147] 27 There was a constant danger to educate the "non-Aryan children" by their teachers due to prohibition by the state [147]. Nonetheless, the risk was worth it and brought them deep satisfaction, as Bondy declared: "It must be emphasized […] that we, as teachers of these children, were constantly aware of the danger to thwart day by day the more and more clear prohibition from the Gestapo to give these 'non-Aryan' children education, and we defied this danger day by day. These years of conspiracy against Hitler's spirit were as dangerous as the direct conspiracy against Hitler himself. To wrestle at least a small group of children from this spirit, to convert the intellectual neglect into the opposite in our small area, was our daily joy and gave us strength to persevere." [147] 28 25 Original text: "So waren wir [die Lehrer und Schüler] eine eigene und einzigartige Partisanengruppe, und wenn auch unsere ‚Heldentaten' nicht mit denen der mit den Waffen Kämpfenden verglichen werden können, so gehören wir dennoch zu den ‚Unbekannten Österreichern', die niemals für Hitler einen Finger rührten, sondern gegen ihn in Wort und Tat unter ständiger und jahrelanger Lebensgefahr für eine bessere österreichische Zukunft kämpften. Mögen auch solche Argumente im Streit um Österreichs Teilnahme am Widerstand gehört werden!" 26  To deal with this miserable daily routine and to escape their hardships, Bondy and the group of teachers and students succeeded keeping up their spirits with gallows humor-fleeing into the cemetery to feel free [147]. He explained their daily life and attitude as follows: "Nobody should be surprised that there were many tragic-comic situations. They resulted from the fact that children always have the tendency towards humor and fun, even when death is at the doorstep-and death was always at our doorstep. So, we loved to go on a trip to the 'fourth gate' of the Central Cemetery [of Vienna] as our destination on beautiful days. Because of the prohibition to use the tram for [my] teachers and students, we had (again under mortal danger) to smuggle ourselves through, or we went by foot the long way. But from the fourth gate began-freedom! Among the dead, we felt safe and without any worries. Never was the holiness of a cemetery more honored as by the often-loud joyfulness of these poor children, for which every park, every meadow, every forest was prohibited by the death penalty." [147] 29 However, Bondy's care for children did not end with the war and extended into his private life. On August 21, 1945, Hugo Bondy officially became the legal guardian of the 16-year-old orphan Frieda Verständig. 30 Her father was Sigmund Verständig, 31 a bank clerk of Jewish faith that was deported to Theresienstadt, where he died on June 18, 1943 [148][149][150][151]. Most likely, Frieda Verständig was a student of Hugo Bondy before she was deported with her father. Frieda Verständig would remain the only child in Bondy's family life.

The lost cause of reinstatement
In the middle of April 1945, Hugo Bondy experienced the end of the war. Vienna was captured and occupied by the Red Army of the Soviet Union. Soon after, on May 25, 1945, Bondy wrote to the faculty of philosophy at the Universität Wien, where he pledged for reinstatement after his expulsion in 1938. He further pointed out that the Austrian Ministry of Education did not manage or reply to his appeals for payments, which were granted by law to him [152]. Regarding Bondy's reinstatement, Prof. Eduard Haschek, as the temporary director of the 2nd Physical Institute, provided his opinion to the dean of the faculty of philosophy on June 20, 1945. Haschek opposed the nomination of Bondy as an Assistent to their institute, claiming that he had already performed moderately in the 1930s. Another possible motivation was that Haschek, as deputy director of the 2nd Physical Institute, did not want Bondy enforced on him and the institute. Hence, Haschek put forward several other reasons to prevent Bondy's reinstatement under his watch [63, 64].
Haschek wrote: "[…] At the present time, when the work at the institute grows from day to day, while in view of the financial situation of the state, it is impossible to increase the number of supportive workers arbitrarily, the reinstatement of Dr. Bondy to his Assistenten position seems, to me, not favorable, and also not suitable as only the temporary director in accordance with my respected strict principle, not to inhibit the free right of disposition for the final director." [63] 32 For Haschek, Bondy should also not receive the position because of money shortage by the state and no jurisdiction by him as only the temporary director. Both arguments can be considered weak. First, the shortage of money by the state was not a concern to the only deputy head of an institute, especially with increasing work. Bondy was, at least on paper, a qualified candidate with work experience in academia and in the institute. Second, Haschek's interference regarding Bondy's employment is incoherent and already 29  Frieda Verständig was to be considered a "Mischling" by the Nazi authorities, her father was of Jewish decent and her mother was considered an "Aryan". In 1942, she was deported to Theresienstadt with her father after her mother's death. She survived Theresienstadt and was freed there in 1945. She never married and had no children. 31 Sigmund Verständig; date and place of birth: September 27, 1875 in Krakau (Kraków), Poland; date and place of death: June 18, 1943 in Theresienstadt (Terezín), Protectorate of Bohemia and Moravia (Czech Republic); faith: unknown to the authors, profession: bank clerk. 32 Original text: "[…] In der jetzigen Zeit, in der am Institut die Arbeit von Tag zu Tag wächst, während es natürlich mit Rücksicht auf die finanzielle Lage des Staates unmöglich ist, die Zahl der Hilfskräfte beliebig zu vermehren, scheint mir die Wiedereinstellung des Dr. Bondy in seine Assistentenstellte nicht günstig und außerdem mit dem von mir streng eingehaltenen Grundsatz als interimistischer Leiter, das freie Verfügungsrecht des künftigen definitiven Vorstandes in keiner Weise zu hemmen, als nicht angebracht." contradicted by his position of a non-interference policy for his successor [63,64].
Eventually, the dean of the faculty of philosophy followed Haschek's advice and declared that while the future director has not been chosen, no decision could be made. Because the dean stalled the reinstatement with his letter on June 25, 1945 [153], Bondy wrote an urgent reply to object. In his answer to the dean from July 3, 1945 [154], Bondy described the circumstances of his situation and reinstatement: "I was discharged from my duty as Assistent at the 1st Physical Institute because of racial-political reasons after the so-called upheaval; after the suspension of the Nazi laws, I considered myself-in accordance with legal regulations-as a Universitäts-Assistent again and made myself available to the head of the Physical Institutes Mister Prof. Haschek. I was not least surprised that the Mister Professor failed to acquire my former service obligations or any other employment in the institute. The justification that I did not accomplish anything scientifically during the last seven years of Nazi reign hurt me. It does not apply at all, since in this time period of bullying and temporary serious plight-I was finally bombed out-I found comfort and courage to survive in the scientific work." [154] 33 Bondy urged further for his earnings as an Assistent since May 1, 1945, due to the emergency situation he was facing [154]. The dean forwarded Bondy's reply to the responsible ministry on July 11, 1945 [155]. Fortunately, Bondy could continue his work as a teacher starting from July 4, 1945 [156].  August 7, 1945 [159]. The only rehabilitation Bondy gathered from the government was the imputation of his exile years from the Universität Wien to his pension and care fund, including the post-war period [160,161]. 34 Hugo Bondy never worked in academia again, but devoted the rest of his life to improve the education system of Austria for future generations.

Education for the Austrian youth
On August 28, 1945, Bondy inhabited the position as head of the division of youth and sport in the State Office-later only division of youth in the Austrian Federal Ministry of Education (Österreichisches Bundesministerium für Unterricht) [162]. Under Ernst Fischer, the State Office should have monitored and guided the Austrian youth movements (Jugendbewegungen) [163]. Bondy described its mission in a book contribution of 1948 as the following: Therefore, Bondy and his division were initiated to fulfill this mission. Hence, Bondy clarified the mission and its goals in a broader historical context as follows: "[… The Austrian Federal Ministry of Education] faced new problems and dealt with tasks that it had not before. From the beginning, it was clear and none of the plentiful evidences were needed that the doctrines of national socialism had fatal impacts on the adolescent youth. Although the HJ [Hitlerjugend-Hitler youth] was not in a strict sense a youth movement, the pressure from outside was very strong and the time of its effect was so long that the poison of Hitler's spirit entered into the souls of a large part of the youth, very often against 33 Original text: "Ich wurde nach dem sogenannten Umbruch aus rassenpolitischen Gründen meines Dienstes als Assistent des I. Physikalischen Institutes enthoben; nach Ausser-Kraftsetzung der Nazigesetze habe ich mich -den gesetzlichen Bestimmungen entsprechend -wieder als Universitäts-Assistent betrachtet und mich dem Leiter der Physikalischen Institute Herrn Prof. Haschek zur Verfügung gestellt. Ich war nicht wenig erstaunt, dass mir der Herr Professor die Uebernahme meine[r] früheren Dienstobliegenheiten oder sonst eine Beschäftigung im Institute versagte. Die Begründung, dass ich während der siebenjähriger Naziherrschaft wissenschaftlich nichts geleistet hätte, hat mich verletzt. Sie trifft gar nicht zu, da ich gerade in dieser von Drangsalierungen und zeitweiliger schwerer Notlage -ich wurde zuguterletzt ausgebombt -erfüllten Zeit in der wissenschaftlichen Arbeit Trost und Mut zum Weiterleben gefunden habe." 34  the will of the affected. The sources of this poisonous stream ended suddenly in 1945, but its impacts cannot be stopped immediately; they can continue latently and are sometimes hard to combat. If in former times the youth and its associations went their own way, the state had not to be concerned about this way. In 1945, it was the absolute purpose of the government to transfer the supervision and governance of the unraveled youth, even outside school, to the responsible Ministry [of Education], to make it responsible that the gradual transition from the state of inner confusion, often depravity, but almost always of aimlessness and lack of ideals, to humanity and democracy, to an Austrian state awareness and a well understood cosmopolitanism, really takes place without interference from outside. [...]" [163] 36 Bondy declared later in the article how the division of youth saw its role and tried to intervene with the youth: "Monitoring the youth movement with respect to possible aftermaths from the fascism era is still in focus. Wherever rudiments of overcome perceptions are displayed, the division of youth must be ready to take a decisive stand and, if necessary, to intervene. Mostly, the form of consulting and, if necessary, warnings should be sufficient. […] The fight against all cultural excesses, against pulp and trash in all aspects of culture has to be strengthened in the interest of the youth. […] Subsequently, the great idea of rapprochement of all people and nations has also to be consolidated in the youth work […]. [...]" [163] 37 In the view of Bondy, the division's role was, in summary, to be the guarding angle for the Austrians youth and its organizations to overcome the Nazi era with its indoctrination and to guide them to the ideals of western civilization. It is impossible to evaluate how much of this was the division's or Bondy's mission, how many of these ideas were his or those from the division, or how loose the division could have acted under Bondy's leadership. Given Bondy's past, it seems that he was personally aligned to a vision and an idea of Austria's future on those principles. For him, it seemed necessary to educate the youth correctly and to prevent the impact of the Nazi ideology and new extreme ideologies in present and future. The past should not repeat itself in any way or form. Therefore, Bondy saw the youth as the vital key for a more just and prosperous society. As a result, he wanted the government to play an active role and intervene, if necessary, on matters of the youth. The government should provide the possibility and set the boundaries within which the youth could feel free and safe to develop an Austrian identity [163]. For Bondy, this may also have been in line with the realization and the ideals of communism at that time.
Following this mission, Bondy initiated and supervised several projects of his division. One representative project for Bondy's work was the Austrian Youth Day (Österreichischer Jugendtag), which was performed for the first time only in Vienna in 1945 with a limited number of youth organizations due to the war. The second Austrian Youth Day of 1946 was of a larger scale and Hugo Bondy advertised it [164][165][166]. In a small newspaper article [166], he promoted the day as follows: "In the fascist era, young people were forcibly pressed into para-military organizations, in which any free expression of opinion was a crime. Tomorrow [the Austrian Youth Day] will not see drilled marching machines, reinforced with daggers, tramping through the streets under timpani rolls and fired up by 'snappy' orders of HJ-leaders; but free, joyful people from all political spectrums and all schools of thought coming together for a joint demonstration of unity.

3
The youth organizations are faced with the difficult task of raising up the Austrian youth again, to educate them into democrats, a task on the fulfillment of which the future of Austria decisively depends. […] The Austrian youth will never again serve as cannon fodder for criminal imperialistic plans and prove that they want to properly comprehend and become acquainted with the new world in the making, after years of intellectual servitude. The [Austrian] youth wants peace, freedom, and prosperity. [...]" [166] 38 For the purpose of the Austrian Youth Day, a first session of a youth parliament with delegates from all youth organizations was further planned. However, Bondy's political idealism met the reality of the post-war period. Due to conflicts between the different Austrian youth organizations as a result of their political leanings, the demonstration ended in a turmoil and the youth parliament was dissolved as only a fraction of delegates participated [164,165,[167][168][169][170][171]. Still, Bondy continued to be engaged with the upbringing and education of the young people of Austria and published a newspaper article on this subject in 1950 [172]. Nevertheless, his dedication to youth work and his membership to the Communist Party of Austria would spark a public controversy in the 1950s.

Red fear of a government official
Hugo Bondy joined the Communist Party of Austria (Kommunistische Partei Österreichs-KPÖ) in April 1945 [59]. The reason for this is unknown to the authors. In the context of his life, it can be assumed that during or after the war he saw communism and the KPÖ as the only alternative to the Nazi party and ideology. The Communist Party of Austria had already been active in the underground before the German occupation of Austria and in clear resistance to the Third Reich.
Nevertheless, Bondy remained, to the authors' knowledge, faithful to Roman Catholicism throughout his life. Siegmund Bondy was a government employee at the university, who usually were not in favor of communism and its ideas and more leaning to the right political spectrum. All of this made Hugo Bondy an unlikely supporter of communism in his youth and perhaps later motivated him not to subscribe fully to the communist ideology, leaving his personal convictions intact. He was later described as a representative of the "Catholic camp" [164]. Nonetheless, Bondy was never a member of a political party before he became a member of the Communist Party of Austria [59]. Until then, he seemed, given his career as an academic, more apolitical.
Other reasons for Bondy's membership to the KPÖ could be more opportunistic. First, he was unemployed in a country destroyed by the war. Second, parts of Vienna and its surroundings or close territories (Lower-Austria, Burgenland, and parts of Upper Austria) were occupied by the Soviet Union. Furthermore, the later communist countries of Czechoslovakia and Hungary bordered these territories. Third, the Communist Party of Austria was supported by the Soviet Union and had a stronger support in industrial regions and cities. Because of this, the KPÖ was the third largest political party in the Second Republic of Austria and was acknowledged for the provisional government. Therefore, the communist party was a not neglectable political force in Vienna and needed educated personnel to govern the country. In conclusion, Bondy was given a good opportunity by the political circumstances, his persecution in the past, and his education. The misery during and after the war was maybe the final driving force towards the Communist Party of Austria. Although, Bondy also likely found the intellectual attitude and theoretical discussions of the party appealing.
After his accession to the Communist Party of Austria and his appointment by Ernst Fischer for the division of youth and sport, Bondy was also active for the KPÖ in 1947 [173]. He published two articles, one in the newspaper of the Soviet occupation force [166] and one in a political left orientated newspaper [172]. However, it seems that his contribution to the Communist Party of Austria was rather small and Bondy focused more on the work in his division.
After WWII, the coalition of the Allies crumbled and the Cold War began, especially with the announcement of the Truman Doctrine in 1947. In Western democracies, the fear of communist spies and underground networks reached a new peak in the 1950s. Anti-communist agitation was used as a political weapon to question the loyalty of political opponents and public figures to their own country and government. Austria was not an exception.
[…] Die österreichische Jugend will sich nie wieder als Kanonenfutter für verbrecherische imperialistische Pläne hergeben und beweisen, daß sie die im Werden befindliche neue Welt, nach Jahren geistiger Knechtschaft, richtig begreifen und kennenlernen will. Die [österreichische] Jugend will den Frieden, Freiheit und Fortschritt. [...]" Nations Educational, Scientific and Cultural Organization) [59,174,175]. As a member of the Communist Party of Austria and a nominee of Ernst Fischer, he represented a target due to his work in government, specifically in regard to his work for the youth and as a representative of Austria in the UNESCO. Several public articles in newspapers followed, attacking Bondy for his political affiliations and spreading fear of communist influence on young people [59]. On December 14, 1952, the newspaper from the conservative Austrian People's Party (Österreichische Volkspartei-ÖVP), Das kleine Volksblatt, wrote: "[… Sektionsrat Dipl.-Ing. Dr. Hugo Bondy is the head of the division of youth in the Austrian Federal Ministry of Education,] who follows strictly the instruction of the Communist Party headquarters and travels as a staid Austrian through the Austrian states to be up to date with the 'extracurricular' youth care, 'naturally only in the interest of the ministry'. He is the 'Austrian public official', who regularly gives courses for the youth leaders and educators and holds presentations. And for that, tax money is spent. And it is this man, […], who, with a mischievous smile, listens to our staid rural school teachers, who appears in flattering kindness to the presentation for his Sektionschef, but behind his back makes threats heard that clearly reveals his People's democratic heart.
[…] He is also the one who brags that nobody can touch him.
[…] [… Dr. Bondy is not even scared] to tell official foreign guests information diametrically opposed to the government's policies, […]. Maybe also the consideration could help here that such circumstances are not any more acceptable for the well-meaning Austrian people, if even the fact is not enough that the Austrian youth should not be exposed to communist infiltrations." [176] 39 On December 15, 1952, Bondy wrote a response to the Federal Minister of Education to counter the allegations [177]: "In recent times, a political smear campaign started against me, which the socialist press had begun, the Salzburger Nachrichten picked up, and the ÖVP-press […] continued. Although no specific allegations were made, because they cannot be made, these articles are still useable to poison the atmosphere and to question my personal honor by accusing me of ill loyal behavior against my office and the state political interests of Austria. It is strange to me that even the ÖVP-press, where one would expect that they are better informed about such matters, takes part in these activities. I therefore ask you, dear Mister Minister, to examine carefully, everything that the division of youth accomplished since its founding in 1945 under my leadership, as well as my attitude on official occasions, in which I had the honor to represent the Federal Ministry of Education publicly. In particular, I must declare the allegations that I 'make threats behind the back of my Sektionschef' and that I 'tell official foreign guests information diametrically opposed to the government's policies' as completely fabricated out of thin air and false. I askalso in the interest of the Ministry [of Education]-to demand evidence for these claims and to expedite the proceeding, since it also concerns my honor as a civil servant." [177] 40 Original text: "In der letzten Zeit hat, von der sozialistischen Presse begonnen, von den Salzburger Nachrichten aufgegriffen und von der ÖVP-Presse […] fortgesetzt, eine politische Hetzkampagne gegen mich begonnen. Wenn auch konkrete Beschuldigungen nicht erhoben werden, weil sie nicht erhoben werden können, so sind diese Artikel doch geeignet, die Atmosphäre zu vergiften und meiner persönlichen Ehre nahezutreten, indem mir illoyales Verhalten gegenüber meiner Dienststelle und den staatspolitischen Interessen Österreichs vorgeworfen wird. Sonderbar berührt es mich, daß auch die ÖVP-Presse, von der man doch annehmen muß, daß sie in dieser Angelegenheit besser informiert sein könnte, sich diesem Treiben angeschlossen hat. Ich bitte Sie daher, sehr geehrter Herr Minister, alles, was die Abteilung Jugend seit ihrer Gründung im Jahre 1945 unter meiner Leitung geleistet hat, sowie auch meine Haltung bei allen offiziellen Anlässen, bei denen ich die Ehre hatte, das Bundesministerium für Unterricht in der Öffentlichkeit zu vertreten, einer genauen Prüfung zu unterziehen. Insbesondere muß ich die Behauptung, daß ich ‚hinter dem Rücken meines Sektionschefs Drohungen hören ließ' und daß ich ‚nicht davor zurückschrecke, offiziellen ausländischen Gästen eine jeder Regierungspolitik diametral entgegengesetzte Auskunft zu erteilen' als völlig aus der Luft geg-werden können, wenn schon die Tatsache unbeachtet bleibt, daß man Oesterreichs Jugend nicht kommunistischen Infiltrationen aussetzen soll." Footnote 39 (continued) However, the pressure increased from other side. The leadership of the Austrian Youth Movement (Österreichische Jugendbewegung-youth organization of the ÖVP) from Lower Austria appealed to the Federal Minister of Education about that matter [178]. They wrote on December 18, 1952: "[… We appeal to you, that] Mister Sektionsrat Bondy, the head of the division of youth, will be transferred to another division. It seemed for the political committee and the delegates [of us] an unsustainable solution to leave the already mentioned gentleman in this leadership position of the division, who is a known communist party member. It must have an unfavorable effect not only domestic but certainly also abroad, if the ministerial care center for the youth is placed in the hands of a convinced communist. [...]" [178] 41 They justified their request for a transfer with an incident, in which Bondy had made unqualified remarks to a representative of the Council of Europe, although they admitted that they were not able to reproduce Bondy's comments literally. Nevertheless, they emphasized that they did not want to harm Bondy or his career in the ministry, but they insisted that he was unbearable as the head of the division of youth, and had to be transferred to another division where he did not have direct contact to the Austrian youth [178].
Two days later, Bondy submitted another statement to the Federal Minister regarding the whole affair and with a possible suitable solution [179]: "[...] I send in advance that I feel completely free of any guilt, any neglect of duty, or [any] violation of loyalty. But I see more and more that under the given circumstances of the political parties against the Minister, it causes him a large embarrassment to hold a member of the KPÖ (not a party official, certainly not a 'leading' figure) for longer as the head of such a politically exposed division, even though he proved to be a flawless, qualified, and at any time loyal civil servant. On the other side, I may speak from my personal situation, from the human side. I was a victim of Nazism for seven years, and rescued myself just into a 'better' time. Now I ran again into the danger of becoming the victim of the reasons of state by no fault of my own like before, only because I am a simple member of a party, which is legally recognized, but in opposition. The departure from the division, built and selflesslyalso in political matters really selflessly-lead by me, I find after a long time of collaboration with my good, diligent staff very difficult; […]. [...]" [179] 42 The departure from the division of youth was obviously already discussed and inevitable. Bondy should be transferred to another division, which was less exposed to the public eye. However, he did not want to leave the impression of a demotion or admission of any guilt. Furthermore, Bondy wanted to get the best out of the situation. Therefore, he proposed a plan to save his and the ministry's face that did not cause any more political attention [179]. Nonetheless, Bondy declared his resignation from the division of youth without insisting on his made suggestions on December 22, 1952 [180]. The Federal Minister of Education accepted the resignation and thanked him for his work in the division. Bondy was then transferred to the division of technical-commercial schooling, where he started on January 1, 1953. No investigation was initiated at any point [181,182]. Bondy was later promoted [183] and more time of his expulsion was acknowledged for the determination of his pension [184]. The pressure from the public dropped. Das kleine Volksblatt wrote satisfactorily on January 15, 1953, that Hugo Bondy was no longer head of the division of youth [185].
In 1956, the political affiliation of Bondy to the Communist Party of Austria ended. The cause for this was the violent suppression of the uprising in Hungary by military forces of the Soviet Union. However, opportunistic reasons may have played a role too. The KPÖ was no longer part of the government, its support by the Austrian people was 41  marginal, and the fear of communism was on a high and counterproductive for a career, especially in the civil service. Above all, Bondy considered his idealism and dream of a better and new world crushed by this military intervention. In a letter to the Austrian Federal Chancellor Josef Klaus, the Federal Minister of Education, Theodor Piffl-Perčević, wrote that Bondy "was always considered a tempering factor among the left-intellectuals" and "follows again the civic path" [59,186,187]. Bondy presumably then focused all his energy on his job in the Austrian Federal Ministry of Education. There, he found still purpose and could try to make a difference for the education of young Austrians.

Devoted to the service
When Hugo Bondy joined the Austrian Federal Ministry of Education on August 22, 1945 [158], he did not know that it would be the start of a twenty years' career in the civil service. In this time period, he published work-related books and articles [172,[188][189][190][191]. He started as the head of the division of youth and sport and applied for the civil servant rank Ministerialsekretär [192]. On November 13, 1947, Bondy was awarded with the official title Sektionsrat [193,194].
For the year 1950, Bondy was evaluated to clarify if he met the qualification requirements for his position. The responsible commission gave him an A (Sehr gut) in their general conclusion on September 18, 1951 [195]. In specific qualifications, it was stated that he was dedicated to diligence, very conscientious, and very reliable and loyal in his service. Furthermore, the commission declared that Bondy was very suitable for the administrative tasks and field service with appliers and partners of the ministry. He was described for that matter in his appearance as calm, prudent, polite, and very tactful. His behavior was stated as impeccable and his success in service was declared as very good [196]. The evaluation contradicts the comments later in the press, which were made in 1952 in consequence of his membership to the Communist Party of Austria.
As a result of this affair, Bondy was transferred to the division of technical-commercial schooling. He received the promotion to the civil servant rank Ministerialrat on June 27, 1953 [197]. While Bondy advanced in work, in his private life his marriage was in crisis. On October 25, 1956, he was officially divorced from his wife after twenty-six years of marriage [198]. The reasons for the divorce are unknown to the authors. However, Bondy remarried on November 24, 1956 Maria Brössler, 43 born Kornherr [31,199,200].
From January 1, 1956, Bondy was the head of a section in his rearranged division [201] and then became the deputy of the division [202]. On July 17, 1958, he was recognized for his work in the Austrian Federal Ministry of Education with the accolade Grand Decoration of Honor for Services to the Republic of Austria (Großes Ehrenzeichen für Verdienste um die Republik Österreich) [203]. To celebrate the sixtieth birthday of Hugo Bondy, his colleagues printed an anniversary book to honor him [201] (see Fig. 4).
In the year 1962, Bondy faced a heart attack. As his personal doctor ordered him to resettle in a healthier environment and he could not find a suitable place in Vienna, he decided to build a house in Bad Goisern [204,205].
Until his retirement in 1965, Bondy was awarded with the Ring of Honor (Ehrenring) for loyal service to the Austrian Federal Ministry of Education [206]. More for his wife, who wanted to see Bondy and his work recognized, he pursued a final promotion to the civil servant rank Sektionschef at the end of his career [207]. The Federal Minister of Education, Theodor Piffl-Perčević, intervened for Bondy's request to the Federal Chancellor, Josef Klaus [186]. For his appeal, Bondy's division also wrote a statement in favor of his service and achievements [208]. Eventually, Bondy was awarded with the title Sektionschef on September 12, 1966 [209,210].
Nothing is known about Hugo Bondy's life in retirement in Bad Goisern. In 1968, he wrote a letter to the Federal Minister of Education regarding a very important personal matter. He asked if the Minister could intervene on his behalf to the Austrian Federal Ministry of Infrastructure and Nationalized Companies (Österreichisches Bundesministerium für Infrastruktur und verstaatlichte Unternehmen) to provide his house with a direct phone land-line. Although many people were waiting for a direct phone connection in Austria during that time, Bondy stated that, for him and his wife, a direct communication was vital considering their age and the place they lived, a remote mountainous area, where the phone would be the only form of communication sometimes in the winter and for emergencies. He already waited for over two years to get connected to the phone network [211]. After filing Bondy's request directly to the responsible minister [212,213], a telephone connection was installed. Hugo Bondy replied with his humble thanks to the Federal Minister of Education for his intervention on paper with his pre-printed personal letterhead that now stated proudly his new telephone number, which he inserted with the typewriter [214]. He remained well connected.
For  [200]. After a long, severe suffering, Hugo Bondy died at the age of eightyfive in the hospital of Hallein on August 9, 1985 [219]. In a final thank you letter from the Austrian Federal Ministry of Education to the manager of the care facility, it was stated that Bondy kept in touch with his former colleagues from the ministry and celebrated his eightieth birthday with them five years earlier [220]. Hugo Bondy was buried on the cemetery of Oberalm, next to his wife [219].

Summary
Hugo Bondy's life is as complex and contradictory as the twentieth century. In science, he contributed important work to the development of mass spectrometers and isotopic research. The design of Bondy and Popper, after the theoretical considerations of Bartky and Dempster, was the first mass spectrometer to use the double-focusing effect on an ion beam for analysis. Therefore, the realization of Bondy's and Popper's mass spectrometer with a direct combination of an electric and magnetic field can be called the Bondy-Popper design (Bartky-Dempster geometry). For mass spectrometers that are limited by space, this geometry is still relevant today as was shown for a miniature mass spectrometer in 2001 [98].
Beyond science, Bondy can be credited for twenty years of dedicated service at the Austrian Federal Ministry of Education to youth work and the school system to overcome the Nazi rule and its impact on later generations. His self-devoted service to the persecuted children in desperate need of guidance during his own suffering showed an inspiring example of humanity and empathy under extraordinary circumstances of persecution. For all of this, it is worth to commemorate him.
Finally, Hugo Bondy's life illustrates the process and the negative consequences of expulsion from science only by prejudice: people are judged not on their abilities and merit, but on their perceived difference, which leads to loss of talent and hampers the progress of science. This questions the very foundation of natural science on empiricism, which advances natural science in the first place and where a judgement is made on facts and not on opinion. However, Bondy's life showed also the importance and value of science and education in troubling times. It is necessary to teach science to be save from false convictions by reason. Hence, it is vital to apply a scientific attitude on the world to progress society. Therefore, Hugo Bondy was a true scientist.  Meaning high school diploma. A specific name in Austria for the high school diploma, which grants access to higher education Ministerialrat Meaning Ministerial Council. A specific title and rank in the civil service of Austria Ministerialsekretär Meaning Ministerial Secretary. A specific title and rank in the civil service of Austria "Mischling ersten Grades" Meaning to be of mixed race or blood, or a half-breed in the first degree. A person (Nazi term) that had two grandparents, who belonged to the Jewish religious community, when the "Nuremberg Laws" were enacted in 1935 and did not fulfill requirements to be classified as a "Jew" Montanistische Hochschule Meaning Higher School in Mining. First and original name of the Montanuniversität Leoben Montanuniversität Leoben Meaning University of Mining in Leoben Nationalratspräsidenten Meaning President of the National Council. A specific Austrian name for speakers of the parliament Nationalsozialistische Deutsche Meaning National Socialist German Workers' Party or Nazi Party. Political party in Arbeiterpartei (NSDAP) Germany in the first half of the 20th century "Nicht-arisch" (Nazi term) Meaning "Non-Aryan". A person which was, by definition of the Nazi laws, not "Aryan" Nieder-Österreichisches Meaning Lower Austria Secondary Education School. A specific school in the Austrian Landes-Realgymnasium school system "Nürnberger Gesetze" (Nazi term) Meaning "Nuremberg Laws". Nazi laws for legal anti-Semitic and racial discrimination enacted in Funding Open access funding provided by Montanuniversität Leoben.

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