It was within the context of this research that he also proposed using a specific wavelength of
light as a reference point for a standard unit of length. He had already established that the
wavelength of light always remained constant, and did not, as was commonly assumed,
depend in any way on the speed of the light source itself. This in turn led to his extensively
discussing Doppler’s theories, proposing that certain analogies between light and sound could
not be made. Here, as of course in all of his theories on light, “aether” still played a central
role. Although van der Willigen’s idea to define a standard unit of length using the
wavelength of light is testimony of his capability of far-reaching insights, he did not know
that this had already been suggested some years earlier by Johann von Lamont and, as in all
other areas he worked in, the honour of a groundbreaking discovery eluded him.
This idea for a new definition of a standard unit of length seems to underscore Gerard
Turner’s conclusion that all van der Willigen’s research at Teylers had been linked to one
theme, the establishment of a standard length.212 Turner concluded this mainly on the basis of
van der Willigen’s acquisition policy. He pointed out that the acquisition of a reversible
pendulum by Repsold and a chronometer by Hohwu, combined with other instruments van
der Willigen had acquired earlier for the collection, would indeed have enabled him to
establish the length of a seconds pendulum, which is one way of establishing a standard
length. What’s more, Turner added, Angstrom had used the standard metre of Uppsala, which
however gained notoriety for being 0,13mm too short, for his work on the solar spectrum
which was published in 1868. Perhaps van der Willigen was hoping to improve on this work.
But van der Willigen was involved in other areas of research as well. One other project to
which van der Willigen devoted some time was the precise measurement of a Foucault
Pendulum’s movements. And in the late 1870s van der Willigen began to show an interest in
magnetism and experimented with strong magnets. In a way he thereby continued work that
both his predecessors at Teylers had already spent time on. Van der Willigen cooperated with
van Wetteren and his associate Elias. These were the instrument makers Logeman had been in
business with. Logeman, however, had left the company in I860.213
All this, incidentally, does not provide any further indication as to why van der Willigen had
the small laboratory building which was mentioned at the beginning of this chapter
constructed in the museum’s garden.
Van der Willigen published the results of his research in a variety of journals.214 One of these
was the Dutch Royal Academy’s Proceedings ( Verslagen en Mededeelingen der Koninklijke
Akademie van Wetenschappen te Amsterdam — Afdeeling Natuurkunde). It has been pointed
out that van der Willigen was pretty much the only member of the Academy of his generation
who published papers based on experimental research and that his papers also constituted
pretty much the only contribution the Academy delivered to physics during this period of its
212 Turner, The Practice o f Science in the Nineteenth Century: Teaching and Research Apparatus in the Teyler
Museum, 14-17.
213 Dijkstra, “Willem Martinus Logeman,” 149.
214 For a full list o f van der Willigen’s publications see: Bakhuyzen, “Nekrolog: Volkert Simon Maarten van der
Willigen,” 106-111.
history.215 He was also a frequent contributor to the prestigious Annalen der Physik und
Chemie, edited by the infamous (amongst contemporary scientists) Johann Christian
Poggendorff.
Finally, many of van der Willigen’s articles were printed in the Archives du Musée Teyler.
This journal, paid for by the Teyler Foundation, had been set up in 1868. As a short statement
printed on the first pages of the first edition of the Archives revealed:
“The Archives of Teyler’s Museum will appear from time to time in installments, which will
contain scientific memoirs and the annual acquisitions of the Library and of the
Palaeontological collections, etc, of the Museum.”21
In other words, the Archives were to serve as a medium through which research that had been
performed with the museum’s collections could be published. Although the minutes of the
Teyler Foundation’s trustees’ meetings do not provide any information as to why this journal
was created or who was the driving force behind its establishment, it can be seen as yet
another symptom of the specialisation of the sciences during this period. More to the point,
the role of learned societies® particularly privately funded learned societies - had dwindled
by the 1860s. Tellingly, for instance, the amount of essays that was submitted in reply to the
prize essay competitions still held by Teylers Second Society in accordance with the
stipulations of Pieter Teyler’s will had been in sharp decline. After 1866, only a handful of
Verhandelingen could ever be published by the Second Society. (Although the Theological
Society did, admittedly, still receive more entries.)217 Generally speaking, prize essay
competitions as a medium through which to publish the results of research efforts had been
replaced by publications in specialised journals (such as Poggendorff s Annalen).
Van der Willigen appears to have had high hopes for the Archives, but they were not fulfilled:
in the introductory remarks to one of his articles he laments - perhaps somewhat naively —
that the authors of a research paper published by the French Académie des Sciences had
recently failed to refer to his work on spectrography, even though he had sent the Academy
the first edition of the Archives, containing his most recent work on this topic. 1 Instead, he
complained, the French Academy had praised a Frenchman for his recent groundbreaking
work. Nevertheless, the Archives were widely circulated - mainly in an exchange of
publications with other societies — and there appears to have been a great deal of interest in
215 Berkel, De Stem van de Wetenschap: Geschiedenis van de Koninklijke Nederlandse Akademie van
Wetenschappen, 1:337 & 341.
2,6 “Les Archives du Musée Teyler paraîtront de temps à temps en cahiers successifs, qui contiendront des
mémoires scientifiques et les augmentations annuelles de la Bibliothèque et des collections Paléontologiques etc.
du Musée.” “Avis,” vol. 1, Archives du Musée Teyler (Harlem: Les Héritiers Loosjes, 1866).
17 For a list o f ail Verhandelingen o f Teyler’s Leamed Societies published before 1978 see: “Teyler" 1778-
1978: studies en bijdragen over Teylers Stichting naar aanleiding van het tweede eeuwfeest. (Haarlem;
Antwerpen: Schuyt, 1978), 37-55.
1 Volkert Simon Maarten van der Willigen, “Rapport servant de premier supplément au mémoire sur la
détermination des longueurs d ’onde du spectre solaire,” vol. 1, Archives du Musée Teyler (Harlem: Les Héritiers
Loosjes, 1866), 62.