Dr. Caroline Emilie Bleeker, physicist and businesswoman

Dr. Caroline Emilie Bleeker (1897-1985),
physicist and businesswoman.

by Marianne (M.I.C.) Offereins

Caroline Bleeker grew up at the beginning of the century in Middelburg, the capital of the province of Zeeland in the Netherlands. After finishing her Physics studies, she founded a physical consultancy, which can be regarded as the predecessor of the present-day TNO (the foundation of applied scientific research). She extended her consultancy with a small factory, in which at first
several scientific instruments were made. Later the assortment was extended with optical equipment. 'Bleeker Optiek' especially became well known for the excellent, solid microscopes that were made, and for the phase contrast microscope, which was invented by Frits Zernike, who received the Nobel Prize in 1956 and manufactured by Bleeker, who also held the patent.

Youth and Studies
In the year 1886 Johannes Lambertus Bleeker, parson of the Evangelical-Lutherian Church in Amsterdam, at the age of forty accepted a call from the church in Middelburg. In March of that year Johannes, his wife Gerhardina Martha Döhne, who was fifteen years younger, and their two daughters Maria Elisabeth (1881) and Bertha Dorothea (1884) settled in the parsonage of the Lutherian church at the 'Bree' near the "Molenwater". Shortly after that a third daughter was born: Johanna Caroline (1887), she was followed by a boy: Otto Diedriek (1892). The family was complete: three daughters and a son and heir; all baby things could be given away. But, after five years, another baby announced itself, and on January 17th 1897 Caroline Emilie was born; by family and friends called Lili.

Caroline was a talented child who learned so much while playing at home, that she could skip the first form of the primary school. If one reads the articles Lili Bleeker wrote years after that in the staffmagazine of the factory NEDOPTIFA
(Nederlandse Optiek en Instrumentenfabriek Dr. C.E. Bleeker) one can only infer that she had a happy childhood, a keen eye, and later an excellent memory.

Her elder sisters left the house to work as teachers, and although her mother wanted Lili to stay at home, she longed to study. Lili wrote about this: " My mother was an old-fashioned housewife, who loved to keep someone with her to help her with her domestic affairs. And that had to be the youngest. I however wanted to 'learn' but a HBS-education (this school can be compared to a grammar school),
was the only study allowed."
From this period dates her lifelong friendship with Adriana W.P. Keg who lived in the neighbourhood since 1902. Later Adriana would marry the, university-trained engineer Murk J. Schoen, who would become of great importance for Caroline and the factory.

After Caroline passed her final exam on the HBS, she stayed home for a year to help her mother. In the meantime she studied Greek and Latin.
In 1916 she finally left for Utrecht, to study Mathematics "out of boredom", because a life filled with domestic tasks did not attract her at all. Certainly in that time for a girl quite an unusual choice. Why Lili switched from mathematics to physics we do not know. It is however clear that the atmosphere at the Physics faculty was open and free and absolutely was of a kind nature towards women 1: "Girls certainly were encouraged and helped by Ornstein 2." (who was one of the professors at the faculty during the time Lili studied in Utrecht.)

She studied successful, and after passing her 'candidaatsexamen' (which can be compared to the Anglo-Saxon 'bachelors'), she tried to earn money as a teacher at a 'Middelbare Meisjesschool' (secondary school for girls), so she could pay for her own study as the Lutheran church could pay her father only a small salary, because the community counted only a mere 338 souls 3. About this job she said: "That was not a great success, I was, I suppose, too young;" she felt too much 'one with the pupils'. Therefore she started giving private lessons. Besides that, from 1919 on, she worked at the astronomical observatory
‘Sonnenburgh’ and as an assistant for various professors in the physics laboratory at the Bijlhouwersstraat. Here she is mentioned as the only senior-assistant in the personnellist of 1926.

During the twenties Caroline also worked on investigations for her thesis, 'Emissie- en dispersiemetingen in de seriespectra der alkalieën'. She was awarded her Doctors title on November 5, 1928 cum laude (with distinction). Her thesis was printed at a printing office owned by Willemse, who was the father of
her fellow-student and partner for life drs. G.J.D.J. (Gerard) Willemse. The couple never married, which, certainly at that time, was highly unusual.
Until now it is not clear what Caroline did during the first time after her promotion. About this period she said in an interview with a journalist: "For a year and a half I did nothing (...) although nothing..., but ach no, you should not write all that in a newspaper."

From several letters written to colleagues by Prof. Ornstein, the professor who supervised her work for her doctor's degree, can be concluded that Caroline was looking for a job. To Prof. Evert Gorter, who was professor in paediatrics in Leiden, Ornstein wrote: "Dear Colleague, answering your letter about a physicist who is able to become an assistant to you, I inform you as follows: In the first place I would want to mention Miss Dr. C.E. Bleeker, Pension 'de Leeuw' Groenekan. Until March last year she was fellow at my laboratory and after that she resigned for personal reasons. She is very intelligent, and well schooled theoretically as well as experimentally4. Caroline however did not get the job. Ornstein went on enquiring for her as appears from a letter by Van Everdingen, extraordinary professor in Meteorology and chief-principal of the KNMI
(Royal Meteorological Institute) who wrote, answering a letter from Ornstein: "In the meantime Miss Bleeker has visited me, and I have promised to inform her about the vacancy [unreadable] though she had some objections against a competition of younger people, I told her, to prefer for several reasons. All concerning I do not feel very much inclined to let her be considered for this job 5.

In an answering letter Ornstein wrote as a post scriptum: "I do regret that things went wrong with Miss Bleeker. Yet she is very talented 6.

The nature of Miss Bleeker's personal difficulties is not clear. She keeps silent about them in the newspaper article in 1954, and her biographer was not able to extract this information, even after numerous interviews with people who knew her intimately.From the material available to us, we can safely conclude that she definitely was conscious of her own capacities, and had no interest in a position below her level. As a matter of fact, she made her own decision and set up her physical consultancy.

Physical consultancy and factory
A year and a half after her degree ceremony, on June 5 1930, Caroline Bleeker opened her 'Physisch Adviesbureau' (physical consultancy) which advised industries and scientific laboratories in the domain of physics and physical instruments. This scientific consultancy - maybe the first in the Netherlands - influenced the Utrecht chemicist H.R. Kruyt as he founded the 'Nederlandsche centrale organisatie voor Toegepast Natuurwetenschappelijk Onderzoek' (TNO) in 1932. About this
Caroline wrote in a letter to her friend ir. M.J. Schoen: "the Physic Consultancy (later the idea was taken over by Kruyt, who founded the TNO) 7.
In September that year she gave the first impulse to her own little factory "with one small lathe and one little drill (...) besides a workbench"8 in a house at the Ferdinand Bolstraat in Utrecht. Some time later the workshop was moved to a number of garages at the 'Laan van Minsweerd'. The business, at first working as a supply industry for laboratories, with one boy as an employee, applied to making series of scientific instruments like galvanometers and precision-resistors. March 1933 the factory was moved to Lange Nieuwstraat 13. In the same year the first catalogue was published. The business prospered and soon the building became too small. Neighbouring houses were bought: Korte Nieuwstraat 13bis (the upper part of the building), Lange Nieuwstraat 17, Oude Gracht 194. All buildings were connected by the gardens. A real labyrinth, which could confuse new employees and visitors; one of the connections went through a cupboard and a long narrow passage. In 1936 the business became a limited partnership, the partners were among others dr. C.E. Bleeker and drs. G.J.D.J. Willemse, who was until that time chief assistant
of the Technical Department at the physics faculty, a very important position. The business had perspective: a year later there were 25 employees.

For years Caroline had been friends with prof. Frits Zernike (1888-1966) from Groningen, who already at that time was famous for his work on optics. Influenced by him, and with some financial support by Zernike, Lili decided to enlarge the business with a department were optical instruments were made - for our country
at that time something completely new. In 1939 the limited partnership was dissolved, and Caroline Bleeker and Gerard Willemse continued the business on joint account under the name 'Nederlandse Optiek- en Instrumentenfabriek Dr.
C.E. Bleeker' (NEDOPTIFA).

The business became renown for the excellent quality of the instruments made, in the Netherlands and abroad. The optical department developed quickly to a success as well, and in 1939 production of a series of 6 x 24 prism-binoculars for the Dutch army began.

In and after the Second World War.
In May 1940 the Germans overran the Netherlands and our country became involved in the Second World War. For Caroline Bleeker's factory a difficult time began. The order of the 6 x 24 binoculars could not be finished, which meant the first great loss for the business. Almost all orders were cancelled, and besides that the factory got completely disoriented by various evacuations. Thanks to the help of before named Murk Schoen - husband of Caroline's lifelong friend from Middelburg
Adriana Keg - part of the employees could be kept working: the did repairs and made piece-work on command 9 All other employees had to be discharged.
Result was: "...in case of illness Miss Bleeker had to replace the person herself" 10. Caroline Bleeker had a large network of scientific contacts in and outside the country, also in Germany, in this respect she was definitely not anti-German. She did however have a distinct antipathy toward the nazi's and the German occupators. She regularly gave explicit expression to her feelings concerning them. She also told in the factory about the News she heard from the (prohibited) English radio. In the building at the Korte Nieuwstraat were persons in hiding, among whom a Jewish lady who before the occupation had worked
in the factory as a telephonist, and later, after the war as a co-worker in the optical department.

In September 1944 the German Feldgendarmerie raided the factory. Presumably they were betrayed by one of the employees; even a name was mentioned in relation to this. Fortunately no incriminating material was found, and Caroline Bleeker, who spoke excellent German, could delay the invaders long enough to save the persons in hiding who escaped through the gardens. Caroline Bleeker and Gerard Willemse were taken for interrogation, but were released the same day. To be certain Caroline ordered all employees to stay away from the factory. Shortly
after, all buildings were looted by the Germans and their accomplices. Gerard Willemse's father was arrested by the Germans. At the moment of that raid he was producing illegal printed matter, on which there was a death penalty. Willemse Sr. was imprisoned and murdered on September 15 in fortress De Bilt.Caroline Bleeker and Gerard Willemse were advised to go in hiding. In the confusion after 'Dolle Dinsdag' (September 6, 1944) they came to be in Zeist (a small town near Utrecht). At the square near the 'Evangelische Broedergemeente' they met
the wife of one of their employees, who found a shelter for them at the home of a physician who lived in the neighbourhood. Lili and Gerard that their factory had produced field-binoculars for the resistance told this Dr. Van Dorp and his wife. As long there was no money from the factory, Caroline Bleeker paid the employees' salaries from her own purse 11 On May 5, 1945, the day of the capitulation, she summoned the remaining employees to come to the factory to clean
up the mess left by the invaders, so they could start working as soon as possible.

Probably her steadfastness during the war, lead to her receiving a reparations-credit from the government, to re-establish a new factory. Moreover she received several orders from the army. About this M.G. Schenk wrote: "Her principled attitude during the occupation costed her the looting of her business, but thanks to her iron energy everything was rebuilt completely. One thing and
another lead to her appointment by Her Majesty the Queen to 'Officer in the Order of Oranje Nassau' 12". The credit had to be paid back to the
last cent - and with interest. She never saw anything back from the money she paid to sustain her employees. The State of the Netherlands did not play a favourable part in the reconstruction of the business in the years after that: when the Japanese started producing cheap microscopes during the fifties, they were preferred over the more solid but more expensive instruments by the Bleeker factory.

The 'Nederlandse Optiek- en Instrumentenfabriek Dr. C.E. Bleeker'
For the new factory the partners Bleeker and Willemse found a place at the Thorbeckelaan in Zeist, in what was by then still a rural environment. On November 18, 1949 the spaciously built factory was opened officially by the minister of Economic Affairs, In 't Veld. Managing directors were Lili Bleeker and her partner Gerard Willemse. Although Lili herself came most into prominence, everything
happened by mutual agreement with Willemse.

Like in Utrecht, Caroline Bleeker in Zeist instructed her employees herself, so she could emphasise those skills the business needed most. For the more general education she later called for a teacher of the grammar school in Zeist. Lili herself taught, among others, algebra and geometry. In that way she got to know
her employees well, and in most cases a very strong bond with the factory could be developed. This bond with the factory was so strong and close that wives of the men working there, seem to have said: "It seems as if you are married to the factory!" In the factory however, people did not just work. Proof of this are programs of concerts, declamatory-evenings, theatrical performances, revue-evenings, puzzle-trips, etc. which are in the Bleeker-archive of Van Ginkel.
Well-known too were the musical-evenings organised at the home of Bleeker and Willemse. Between Caroline Bleeker and her employees there usually was a relationship of trust which is evidenced by personnel-members remarking that, in case of difficulties, "(..) one rather speaks about it with Miss Bleeker herself"13 In the same time she most certainly ruled the roost, so there was an evident distance. All products leaving the factory, were controlled by the managing director herself and by her co-worker dr. Van Zuylen, but of course dr. Bleeker had the final responsibility. At the slightest imperfection the product in question was kept behind, and did not leave the factory. Between 1945 and 1955 the factory extended to a staffing of about 150 persons. During that time Marie van der Kolf wrote in her study about women with a university-education: quot;A special position is taken by dr. C.E. Bleeker as the managing director of a business, both as there are only a few women working as such, and because of the scientific basis of this concern, where instruments for scientific purposes are made in the area of optics and measuring instruments, and are provided to scientific institutions all over the world14."

Bleeker and the phase contrast microscope
Caroline Bleeker's factory was the first in the world to produce complete phase contrast microscopes. This was possible because of the close co-operation between the inventor of this instrument, the aforenamed Frits Zernike and Bleeker. Together Bleeker and Zernike owned a patent on this microscope, which was requested in 1947 and granted in 1962. When in 1953, Zernike was awarded the Nobel
Prize for the phase contrast microscope, the factory 'Bleeker' where the microscope was made, shared in the honour.

The year 1953 was not only important for Caroline's business in connection with Zernike's Nobel Prize. In November of that year it was 25 years ago that she received her Doctors title. The November-issue of the staffmagazine 'De Loupe' (the looking-glass) reported in detail about her honouring by the staff.

We can read among others: "If that day had not been, all our lives would have become completely different. It is therefore that with sincere pride we have given our congratulations to Miss Bleeker"15.During the speeches several notable characteristics of Caroline Bleeker's management were under discussion. One of the speakers observed: "Without doubt you belong to the outdistancing women, who did help along the emancipation of women in today's society."16 One of the ladies "emphasised the fact that, Miss Bleeker on a large scale gives opportunity to young women of all degrees of education, to co-operate in the factory, Miss Bleeker has been able to develop
something which equalises the relations between the sexes."17In her speech of thanks Lili told not to see any merit in celebrating a jubilee: "If one only waits quietly and lives long enough, it just comes of its own accord." Moreover "(...) she hoped that in due time the proportion between men and women would be about fifty-fifty."18

That she meant it can also be concluded from the documents. Already in the annual report of 1940-1941 is mentioned that: "in our factory more and more female labourers will find a place."19

The final years
The years 1960-1964 have been years of extremes. There was recognition on the highest levels: Queen Juliana came to visit the factory. The business had become economically weak. The results were bad. The marketing of the very venerable product could not be handled professionally because of lack of means. Caroline
did not show any understanding for the changing labour-conditions, and she could not get on with the trade-unions. Because she retarded the rises of wages, her specialists were bought away by other concerns like Philips and Euratom. A tense relationship with the Board of Directors developed. Caroline signified that working became physically too much for her as well (by then she was over sixty years old). After ample consideration the Board of Directors decided that Caroline Bleeker and Gerard Willemse were granted honourable discharge as managing directors of the factory. On December 15, 1963 the business-connections were informed and on December 31, 1963 both directors resigned. At five o'clock in
the afternoon they left the factory; all orders were settled there wasn't any work waiting. The founders of the factory would never return. Only Caroline would occasionally visit a reception of her former employees.

From letters customers of the factory sent on the occasion of Caroline Bleeker and Gerard Willemse leaving the firm, appears how much people appreciated the factory.
So in a letter from N.V. Philips Gloeilampenfabriek in Eindhoven can be read that: "we are having difficulties imagining the Nederlandse Optiek en Instrumentenfabriek without the two of you, who have impressed such a very special personal stamp on this concern. With much pleasure we think back about the many years that we have been able to work together with you, and we would like express out gratitude for the extraordinary way in which you have carried out
our orders as a good supplier.20

The working in the factory continued under management of mr. A. Nolke, but finally was taken over by the 'Oude Delft' from Delft. On March 1, 1978 the factory in Zeist closed down. Several old employees found new fields of activity at the Faculty of Physics and Astronomy at the Utrecht University in Utrecht, where
their skill is highly appreciated. The instruments made in the factory witness great quality.

So the phase-contrast microscopes, bought round 1955 by the University of Utrecht on behalf of the physics faculty, are being used until this day at the microscopy-practicum, and have proven to be completely 'student proof'.

After they had retired from the business, Caroline Bleeker and Gerard Willemse could finally dedicate themselves to their hobbies, for which they hardly had the time during their working life. In 1980 Willemse died because of a cardiovascular disease. Caroline survived her partner for five years. In the last years of her life she suffered from a serious form of Alzheimer's disease. It is tragic, that at her funeral not a word was spoken about her life-work: the factory.
On the grave at the cemetery in Zeist until a short time ago were only the name and the date of birth of Gerard Willemse. Thanks to Gijs van Ginkel finally Caroline, who is buried in the same grave, since a few month is mentioned as well.

Caroline Bleeker
From the available documents and the stories comes a clear picture of the factory, and the work of Caroline Bleeker. As her personality is concerned, the picture becomes much fainter. The opinions differ strongly: a "dominant woman" who was "clearly the boss" at the factory, in this respect she did not differ from many of her contemporaries in a similar position. She could badger a
person 'the blood from under the nails'. Her 'Bukkums' (utterly unpleasant reprimands) were notorious. Contrary to that are remarks like the one from her successor, mr. Nolke, about her attitude during the war: "fundamental of the purest gold", and from the quoted newspaper article becomes evident that employees could very well talk to her about their problems.

Within the factory she insisted to being addressed as Miss Bleeker, not as Doctor Bleeker, and in the staffmagazine De Loupe she started a feature 'Van vrouw tot vrouw' (from woman to woman). But that does not mean that she was willing to accept the traditional female image for herself. She was
the manager of the factory and as such she came into prominence. Although her fellowmanager was her partner, she did not marry him. Why they did not take this step, will always remain a question.

Caroline Bleeker very well stood her ground in a male dominated society. This has not always been easy for her, as can be concluded from a passage in a letter she wrote on February 3, 1938 to the then prime-minister H. Colijn: "Being a woman definitely did not make things easier, but I have tried in my own way to help from schooled labourers, who enjoy their work21".

On March 25, 1998 at the University campus De Uithof in Utrecht, for the first time a building is named after a woman: the instrument manufactory of the Physics Faculty will be the "Caroline Bleekergebouw" (Caroline Bleeker-building)