cannot deny that he was a social climber, and his ascension was in large part due to the
success of his scientific activities.
That he was aware of all this transpires from a variety of his activities and statements. One
example is what can almost only be described as his vigorous campaign to be elected to the
Royal Society. Another instance in which it becomes clear that van Marum was aware of
the wider implications of his statements is provided by the fact that he is the only member of
the Second Society ever to remonstrate the minutes of a previous meeting.138
Perhaps the best example, however, is again provided by the series of lectures he gave over
the course of the years. All of these could in fact be construed as serving as the means to an
end - the end, more precisely, of ensuring potential patrons’ goodwill and enhancing the
lecturers’, i.e. van Marum’s, reputation.
His appointment as town lecturer for instance ensured that he could build a network amongst
all those interested in experimental science in Haarlem, many of which, such as Bamaart or
even van Zeebergh, were members of the town’s elite.
His series of lectures for the trustees and members of Teylers Second Society ensured that
they did not lose interest in the collections van Marum was acquiring - and hoping to expand
E with their support, and that they understood — or were at least susceptible to — his arguments
as to why specific acquisitions would have to be made in the future.
Finally, considered from a political standpoint, van Marum’s public lectures given between
1795 and 1797, i.e. in the aftermath of the French occupation of the Dutch Republic, are the
most intriguing. It has already been mentioned how it is noticeable that he emphasises the
potential practical benefits of all research more than he does in any of his other lectures.
However, it has also been made clear that in doing so van Marum did not have to betray any
of the principles he had previously held. So in how far his advocacy of utilitarian ideals in
these lectures was genuine, and in how far it was a matter of circumstance, is difficult to
determine exactly.139
What is clear, however, is that van Marum was well aware of the changes in the political
climate around him, and what potential impact they had on the overall status of research. It is
interesting to chart his reaction in the immediate aftermath of the French Army’s arrival: he
had started giving a series of lectures on chemistry to the trustees in November 1794.140 He
had even gone to the bother of having parts of something akin to a textbook on chemistry by
Fourcroy translated and printed in instalments, so that all of his listeners were, literally, on the
same page.
137 Levere, ‘T h e Royal Society o f London.”
138 “Notulen Tweede Genootschap”, 12.02.1790, Haarlem, ATS, vol. 1382.
Others have tried before. Mijnhardt for instance does not agree with Levere’s assessment that van Marum
emphasised the benefits o f his research for society first and foremost out o f opportunism: Mijnhardt, Tot heil van
I menschdom: culturele genootschappen in Nederland, 1750-1815, 321.
Lectiones Physico-chemicae, juxta Fourcroy Philos. Chem., ut et De inflammatione et combustine legni,
alcorumque combustulium et de extinctione incendiorum”, 1794-1795, Haarlem, NHA, Archief van Marum voi
529, nr. 12.
By the end of January 1795, van Marum had given six, presumably one-hour long, lectures -
and the French had occupied Haarlem. During the last two lectures van Marum had already
started talking about his newly devised methods for extinguishing fires rather than chemistry,
and perhaps he was thereby preparing the ground for what was to come: on February 1 , van
Marum radically changed the tone of his lectures. According to the transcript, he now
addressed the trustees as “fellow citizens” (Medeburgers); and rather than printed, translated
excerpts from Fourcroy’s book, the lecture notes now consisted of what seem to be hastily
written sheets of paper; finally, van Marum blatantly emphasised the benefit his fire
extinguisher had brought society, even professing that anyone who wanted to could come and
see the model he kept at home with his own eyes - perhaps he was trying to show he had
absolutely nothing to hide.
So van Marum was clearly no longer just addressing the trustees through his lectures. It is
worth bearing this in mind when considering what is perhaps the most interesting aspect of
the series of lectures van Marum began to give later that year: the unprecedented (for van
Marum) size of the audience. The exact size is difficult to determine, although his listeners
must have numbered about a hundred, because the venue of his lectures is known: the
Reformed church in Haarlem at the Helmbrekerssteeg; the building has since been
demolished.141 (Interestingly, van Marum had asked the Mennonite parish first whether he
could use a church of theirs at the Peuzelaarsteeg as a venue but his request was rejected. )
Another indication that the audience was not only large but also diverse is provided by a slip
of paper that has been preserved between van Marum’s notes, with a statement evidently
prepared by him that is worth quoting in full:
“As some Young people have abused the freedom granted to them to attend these lectures,
and have behaved improperly during recent lectures, to the annoyance of many Citizens, in
future no young people under 15 years old will be admitted to these lectures even if they have
tickets, except only those who are brought along by their Father or their Guardian or by one
of their relatives, who keep them near them and under their supervision. Young people under
15 years old, who are not accompanied by a father, guardian or relative, who keep them near
them and under their supervision will therefore, to prevent further disorder and disturbances,
be held back at the door by the stewards.”143
Note how “tickets” were evidently required to attend the lectures.
141 On this bulding see: P. L. Slis, De Remonstrantse Broederschap: biografische naamlijst, 1905-2005:
gemeenten, landelijke organen, predikanten en proponenten, publicaties (Delft: Eburon, 2006), 61.
Simon Leendert Verheus, Naarstig en vroom: Doopsgezinden in Haarlem 1530-1930 (Haarlem: Rombach
Boeken Beeid, 1993), 129.
143 “Vermits eenige Jonge lieden misbruik gemaakt hebben van de hun verleende vrijheid om deeze lessen bij te
woonen, en zieh bij de laatste lessen, tot hindemisse voor veele Burgers, onbehoorlijk gedraagen hebben, zo
zullen voortaan geene jonge lieden beneden de 15 Jaaren ofschoon zij billets hebben, tot deeze lessen worden
toegelaaten, dan alleen die geenen, die meegebracht worden o f door hun Vader o f door hun Gouverneur o f door
iemand van hunne naastbestaanden, die hun bij zieh en onder hun opzicht houden. De Jonge leeden beneden de
15 Jaaren, welke niet vergezeld zijn van vader voogt o f nabestaand vriend, die hun bij zieh en onder zijn opzicht
wil houden, zullen derhalven, ter voorkooming van verdere stoornisse en ongeregeldheid, door de oppassers bij
de deure worden teruggehouden.” “Openbare lessen in 1795 & 1796”, 20.01.1796, Haarlem, NHA, Archief van
Marum, vol.529, nr. 12.