This biography, written by J J O’Connor and E F Robertson, has been republished with permission from the School of Mathematics and Statistics at the University of St Andrews, Scotland.
Born: 22 October 1898, United States
Died: 14 December 1987
Country most active: United States
Also known as: Anna Marguerite Marie Lehr
Marguerite Lehr never seems to have used the names “Anna” or “Maria” although she did write one article under the name “A Marguerite Lehr” and her full name appears on her passport application. She was the daughter of George Lehr (born October 1870) and Margaret Kreuder (born August 1871). They had married in 1897 and had five children: Marguerite Lehr (1898-1987), the subject of this biography; Elizabeth Lehr (1900-1985), Charollete Lehr (1904-1967), who was also known as Charlotte, Charles G K Lehr (1908-1993) and George Kreuder Lehr (1911-1996). George Lehr was a grocer who had been born in König, Hesse, Darmstadt, Germany and emigrated to the United States in either 1890 or 1892 (both dates appear on official forms). His wife Margaret had been born in Maryland in the United States to German parents. Before giving details of Marguerite’s biography, let us give some details of her siblings. Elizabeth became an instructor in a school, Charollete became a librarian in the Enoch Pratt Library, Charles became a draftsman working for telephone companies, and George Kreuder Lehr became a bookkeeper for a metal firm and married Jane Leigh Warner in 1943. These occupations are as given in the 1930 US census, when all five children are still living at home with their parents at 255 Mallow Hill Road, Baltimore, Maryland.
Even before beginning her school education, Marguerite was fluent in German:-
I knew German from the time I was four; I grew up in a German church. German wasn’t talked at home because my father didn’t want that.
Marguerite was educated in Baltimore, attending both primary and secondary schools in that city. She recounted:-
The first and only thing I ever failed in school was the first quarter of algebra. And I know why, now … But I could be docile and learn roles, so I passed the second quarter with a 95.
She graduated from Western High School, Baltimore in 1915. This girls’ high school had been founded in 1844 and still exists today, being now the oldest all-girls High School in the United States. After graduating, she began studying at Goucher College where she majored in mathematics. She was strongly influenced by Clara Bacon who taught many of the courses Lehr studied. Lehr graduated with a B.A. in 1919:-
“Ability in a man is knowledge.” Because she was one “to strive, to seek, to find and not to yield,” Marguerite received the first letter of the alphabet as a steady academic diet. The same principle inspired her work on Kalends [the College student publication] and enabled her to take a vigorous part in class athletics.
After graduating:-
… she had planned to continue her studies at Johns Hopkins University “until an instance of Dr Bacon’s unceasing interest in the careers of all her students changed that plan more radically than she (I think!) or I foresaw”. Bacon suggested she apply for a position at Bryn Mawr College as an assistant to Charlotte Scott.
Being an assistant to Charlotte Scott was a rather different experience for Lehr than that of a usual assistantship since, by this time, Scott was completely deaf. This meant that Lehr had to answer questions students asked during Scott’s lectures and she also had to hold office hours for Scott. In fact, she had two roles, half time for each, during the two academic years 1919-21, one being Charlotte Scott’s assistant and the other being a graduate student studying for a Ph.D. advised by Charlotte Scott. She was awarded the M Carey Thomas European fellowship to fund her studies in Europe in 1921-22 but she chose to postpone this, spending the two years 1921-23 at Bryn Mawr College, the first as a ‘fellow in mathematics’ and the second as a ‘scholar in mathematics’. During these two years she completed all the requirements for a Ph.D. except completing writing her thesis. The M Carey Thomas European fellowship allowed her to spend 1923-24 in Rome and she sailed from New York on the SS President Arthur on 16 June 1923. In Rome she studied with Guido Castelnuovo, Federigo Enriques, and Vito Volterra.
Back at Bryn Mawr in 1924, Lehr was appointed as an Instructor in Mathematics and, the next year she was awarded her Ph.D. by Bryn Mawr for her thesis The plane quintic with five cusps. The Introduction begins as follows:-
The quintic with five cusps (characterised by the Plücker numbers m=n=κ=i=5;ν=τ=0;ρ=1m = n = kappa = i = 5; nu = tau = 0; rho = 1m=n=κ=i=5;ν=τ=0;ρ=1) has been considered by del Pezzo, Field and Basset. Field gives a general descriptive account of the appearance of the curve under various conditions on the coefficients in its equation; Basset mentions it as the limiting case under quintics with five nodes; but neither paper gives a detailed study of the curve. In such a study the del Pezzo work is fundamental. Starting with the fact that a quintic with five cusps may be obtained by quadratic transformation from a quartic with two cusps, in- and circumscribed to the triangle of reference, he proves that the quintic is uniquely determined by its five cusps.
In the present investigation, which takes as starting point the del Pezzo work, it is proved that if five points in the plane are given as cusps on a quintic, the curve thus uniquely determined is unipartite, with the five cusps and five inflexions occurring alternately. Moreover, it is shown that from the five given points the cuspidal tangents, the inflexions, the inflexional tangents, as well as a series of ordinary points on the quintic, may be obtained by linear constructions.
In 1929 she was promoted to associate professor and spent 1931-32 as fellow-by-courtesy at Johns Hopkins University and attended lectures by Oscar Zariski. Before returning to Bryn Mawr, she spent the summer in Europe:-
Marguerite Lehr and a friend motored through the centre of France down the Riviera to Rome, up through Sienna and Assisi to Switzerland, through Rothenburg, Heidelberg, etc., to Belgium and back to Havre.
In fact while in Switzerland she attended the International Congress of Mathematicians in Zurich in September 1932. This was the second International Congress of Mathematicians that Lehr had attended, having been at the 1928 Congress in Bologna in September of that year.
She published two further paper: (with Virgil Snyder) Generating involutions of infinite discontinuous Cremona groups of S4S_{4}S4 which leave a general cubic variety invariant (1931) and Regular linear systems of curves with singularities of a given curve as base points (1932). This second paper was the result of her efforts to generalise work presented by Zariski in the lectures she had attended at Johns Hopkins University. In 1935 she was promoted to assistant professor, then in 1937 to associate professor. She wrote about her career in 1970:-
Only at Bryn Mawr, with its full graduate school, would a woman of my generation, in mathematics, have had graduate level courses to give, from the first – regardless of rank. My engagement was with mathematics, not ‘teaching,’ consequently I refused any and all feelers in administration or editing in spite of slow promotion! But the choice was mine – I wanted the full range of thought, live, not text-book concerns.
Lehr became a member of the American Association of University Women and was the speaker at the annual meeting of the College Women’s Club, Montclair, New Jersey, on 14 April 1939. She also gave talks in Boston, Detroit, and Virginia as she gained fame as an excellent speaker. During World War II he was involved in war work which she explained in a letter:-
I just found your post card of 26 March 1942 in my ‘unanswered’ clip, and am sending you a note about my latest experience – quite exciting and rather challenging. Under the Engineering, Science, and Management War Training program a course in maps from aerial photographs (properly called photogrammetry, I gather!) was established this summer, on the Bryn Mawr campus under the direction of three geologists and me … and on my side I put in three incredibly packed weeks, teaching each of two sections three hours math a day, to cover a kind of minimum set of notions which underlie mapping problems. The class of 40 ran from 17 to 58 in age; from high school youngsters whose pencils dripped trigonometry to Commercial artists who shivered at the thought of algebra – but did they work! And did I learn a lot!
She also taught in a V-12 Navy College Training Program at Swarthmore College. It must have been a difficult decision by Swarthmore, as a Quaker institution traditionally against war, to become involved in this program.
Let us take an example of Lehr’s teaching commitments at Bryn Mawr by looking at 1947-48. She gave three lectures and three hours laboratory work each week for a ‘Statistics’ course delivered to Economics, Sociology and Social Economy. A brief syllabus is:-
Descriptive statistics; distributions; mean values; dispersion; elements of probability, of sampling, and of time series. The necessary mathematics is developed in the course.
For Mathematics in session 1947-48 she was involved in teaching ‘Plane Analytic Geometry’ to first year students, ‘Differential Calculus’ to first year students, ‘Second Year Calculus’ to second year students, ‘Theory of Equations, Solid Analytical Geometry’ to second year students, ‘Theory of Probability and Statistics’ to second year students, ‘Advanced Geometry’ to third year students, and ‘Advanced Algebra’ to third year students.
Perhaps Lehr became best known for her pioneering work as one of the earliest presenters of mathematics on television in 1952-53. WFIL, a broadcast radio station from Philadelphia, Pennsylvania, had joined with twenty-five different institutions in presenting University of the Air over Philadelphia’s Channel 6. Bryn Mawr asked Lehr if she would present a course on mathematics, one of the courses with fifteen lectures. She described her course, called Invitation to Mathematics:-
The syllabus contained a brief introduction and a two-hundred word section for each week, with abstract and three references selected to offer wide range of treatment, and as much further bibliography as possible in the strict text or treatise sense. Any one sending for the syllabus was already interested in at least one of the ten subjects; the abstracts were therefore intended to catch attention by questions raised, while the range of reference would (I hoped) reassure and serve a more informed reader. This was one device for coping with the unknown spread of mathematical sophistication in the potential audience.
Her syllabus begins:-
Most people associate mathematics with getting answers or giving proofs, and it is easy to see why. Mathematics does set up good rules for getting quick answers, and does accumulate good reasons for trusting those rules. But the life of the enterprise is inquiry; as we learn how to ask good questions, answers come, and often more powerfully than when we strain for them. So these talks are concerned with raising questions – questions of practical import or pure curiosity – questions about number, space, pattern, logic, which mathematicians know have paid off in increasing our comprehension of the world we live in. You are wrong if you think questions of this kind are special, technical, occurring only to a few gifted people. Almost every small child does things, and asks about things, which touch such mathematical sides of experience. He may be hoping for a rule (what to do); he may be groping for a reason (why it works); mathematics itself swings between rules and reasons. In these talks, children’s casual remarks will often be used, for illumination or to surprise you into an attitude of observant curiosity. Even the dictionary, under “mathematic – fr. Greek” gives first mathematikos – disposed to learn, and only second mathemata – things learned.
The following citation for Lehr receiving the Goucher Alumnae Achievement Award in 1954 is given:-
Able scholar and inspiring teacher, cherishing the best in classical education but not afraid to explore and utilise new ideas and methods, you have made notable contributions to education not only by helping others to understand the nature of mathematics and its role in the modern world, but also by demonstrating and explaining the discipline of scholarship and its intrinsic values.
Her success in the television course Invitation to Mathematics led to Lehr becoming a member of the Mathematical Association of America’s Committee on Film Project which produced a series of films aimed at both teachers and students. She was also hired in 1957 by NBC as a consultant for a television series they produced with presenters who included Emil Artin, H S M Coxeter, Saunders Mac Lane, William Feller, and Richard Courant.
In 1958-59 Lehr chaired the Philadelphia Section of the Mathematical Association of America. She was also Mathematical Association of America visiting lecturer making a major lecture tour:-
Marguerite Lehr has added another to her long list of outstanding achievements. This time she was loaned by Bryn Mawr College to give short courses for advanced students of exceptional ability in other colleges. Last fall she was a visiting professor at New England colleges, and on March 15 she started on a trip to some 15 colleges in the mid-west.
Lehr retired from Bryn Mawr in 1967 and, on her retirement, received the Christine R and Mary F Lindback Award:-
… in recognition of her brilliance as a teacher, for which generations of students will remember her.
As to her interests other than mathematics, she lists the following in 1961:-
… attempts at translation from French, German, Italian … upholstering and other house projects (some of which do oddly have a math side, too), I’m not a bad carpenter and [love] gardening in Maine.
We should balance this, however, with her own description of her passion for mathematics:-
Once a woman asked me, “Are you a mathematician?” The big words, I think, belong to the big things. So I said, “No, but I spend most of my waking hours thinking about mathematics, and sometimes sleeping hours too.” I didn’t know Paul Levy was at my shoulder. He said in his nice French, “But you know very well what mathematics is … You do the dance called ‘thinking’ in front of them. And they learn. They don’t all learn the same thing, but that doesn’t matter.” He looked puzzled, and then he exclaimed, “Ah, the little articles! All those little articles!”
The years of her retirement are described:-
In 1968, the year after she retired, Lehr was living in Salisbury, Maryland, where her sister Charlotte had been living until her death after a lengthy illness in August 1967. In May 1971 Lehr reported to Bryn Mawr from Baltimore that “I am gone from Salisbury a great deal.” Part of that time is likely to have been in Manset on Mount Desert Island in Maine, which she described for her 1954 article in the Bryn Mawr Alumnae Bulletin, as “next to Mathematics, her greatest obsession.” In November 1972, Marguerite Lehr moved from Salisbury back to Bryn Mawr, Pennsylvania.
Following her death, a memorial service was held in the Episcopal Church of the Redeemer in Bryn Mawr, a church with which she had been actively involved for many years. Gifts from many former students led to the Marguerite Lehr Scholarship Fund being established in Bryn Mawr College in 1988.