Laatst bewerkt: 6 December 2023

History (old)

This is an account of the lecture given by Marcel van Daalen on the alumni-evening of August 2017. For the expanded history, please see our history page.

The history of De Leidsche Flesch, the story behind the periodicals. Almost any Flesch member could tell you what the source of the name of this noble study association comes from: in 1746, Pieter van Musschenbroeck or his assistant invented the first capacitor. His collegue Abbé Nollet called it a Leyden Jar.


Intermezzo: a Leyden Jara Leyden jar

The Leyden Jar is the first type of capacitor. This was invented in 1746 by Pieter van Musschenbroeck or his assistant. A year before a similar method to store electrical charge was invented by the German Ewald Georg van Kleist, but since Van Musschenbroeck published his accounts, his invention was globally called the Leyden Jar.

The Leyden Jar is a wide jar with tinfoil coating on the inside. The bottle is filled with (conductive) water. The glass of the bottle isolates and acts as a dielectric. The top of the bottle has a sphere-shaped electrode which has contact with the water in the jar. Charge can be added or taken via the sphere. A Leyden Jar can be charged by an electrolise machine like a Van de Graaffgenerator. With the charge that is stored in a Leyden Jar, spectacular and dangerous experiments can be done. The English physicist William Watson improved the design of the Leyden Jar by coating the inside and outside of the jar with metalfoil. Leyden jars that are parallel switched are called a battery. Such a battery has a larger capacity and thus can contain more charge. The Leyden Jar was used for entertainment in public experiments, at which the public got a shock, also called a battery.


The name was there, but the association only began 177 years later. Then, on the 25th of april 1923, Paul Ehrenfest and a group of entrepreneurial students founded a study association for physical and mathematical students in Leiden: The Leyden Jar, an organisation that would make sure that bèta students had a place to come together, discuss education and enlighten through lectures. 

And now the history of the association becomes harder to determine. We know De Leidsche Flesch was a small association (less than 100 members) for a long time and we know that De Leidsche Flesch became increasingly popular regarding courses and maintaining the quality of the education. This was the case until 1960/1961. In one of these years, a small journal was published. In the five till ten years before this publication, the amount of members of De Leidsche Flesch increased a lot and the desire to set up disputes raised. The life around these disputes became more important for members of De Leidsche Flesch and more activities are organised. This raised the need for the ‘periodiek’ . These ‘periodieken’ filled a large part of the archive of De Leidsche Flesch. Almost no photos exist from this period and extracting information from letters and minutes seems almost impossible. The first periodiek uses A5-format and is only a few pages long. However, this will change. Unfortunately, not everybody was satisfied by the first publication. There is more potential. Consequently, the format was changed. In 1961, the new name “Nieuwe Flesch Courant” became in use. As of 1963, this name was substituted by “Leidsche Flesch Courant”. In one of these publications, our honorary member Jo Hermans, is mentioned as head of the Dies Committee.The papers were published one to three times per month and contain 10 to 15 pages. The contents vary widely in structure. Though scientific sections are published, along with small reports of members, about e.g. activities, the progress of their study or the educational meetings. Furthermore, the still-used “mentoraat” is introduced and trainings are given by senior students. A report of 1963 tells us about a study trip to Germany and in 1967, a special edition with a special study guide is released. In this guide, the descriptions of all courses are found, but this time also advices of students who already followed these courses are included. This idea is still a present topic, so it’s nice to see that this idea is more than forty years old.

Anyway, the conclusion is clear: De Leidsche Flesch is in a good state. De Leidsche Flesch is growing, but times are changing. Not lang after the start of the study year 1967/1968, many are disappointed by the new editors of the Leidsche Flesch Courant and these editors are dismissed. In the first edition of the new editors, led by Frank Israël, former faculty director of astronomy, a preface is written by the former board, stating that the former editorial committee was incompetent, followed by a preface of Frank Israel, stating that the dismissal of the former board was justified, along with an explanation. The Leidsche Flesch Courant seems to have reached an all-time minimum, it has become a medium for jokes instead of the serious article that it once was, containing in-depthness and raising discussions. This was soon realized. After the Dies Natalis of 1968, a four-paged article is put in the paper, filled with criticism related to the active members and the Lustrum Committee. A whole new perspective of the association is sketched. The board is negligent, there are not enough active members and the general mood is lazy. Especially, women are less active and the Lustrum Committee is the worst: the secretary has done nothing except losing the minutes. The head of the board is very busy, but not helping the committee and the rest is doing nothing. The door knobs, acquired by sponsoring, were used in the houses of the committee members and the few activities of the Dies that were organised, failed. Only the ending party, which was somewhat a success. The board plead a change in mentality in the association. If this would not change, De Leidsche Flesch would disappear.

At this points, the structure of De Leidsche Flesch is still the same: there are numerous subsets with monthly activities and everybody is expected to be a member of a subset. In the special edition for first-year students, the following subsets are presented: “Sickbock”, a subset for men named after Olivier B. Bommel. The original objective of this subset was to encourage the members to form new subsets, but it remained in existence after this year. “Q.E.D.”: the oldest subset of De Leidsche Flesch. Originally, it was a formal subset in which new members first had to prove a mathematical theorem. In 1968, the objective is to create a nice ambience. “Bolwerk m”, created in 1956 as the opposite of Q.E.D.: students who want to become a member of this subset, first had to prove their capabilities not regarding mathematics. “M” represented the word “muze”. “Ha-nu!”, a subset created in 1958. “C.G.S.”, a subset for men established in 1962. “Nobel”, a mixed subset established in 1959. So, in total a number of six active subsets, with a seventh subset upcoming. But Israel was right, in the years after, the number of active members is decreasing, along with the number of activities and the number of subsets: in 1969/1970, the oldest subset (Q.E.D.) passes away and the seventh subset was never established. New boards are harder and harder to find. Around 1970, De Leidsche Flesch almost came to an end, until Cyp van de Bult promised the board to find a new board within one week. He was successful. One of the members of his boards later became his wife.

Unfortunately, the problems are still not solved and even become worse. Another problem was that the membership fee had to paid by year. So, when people registered themselves for De Leidsche Flesch during the El Cid in 1972, they did not continue their membership after one year, because no activities were organised after the introduction week of the association.  In 1973, the association was nowhere to be found during El Cid, resulting in no new members. The introduction week was also not organised. The board did nothing. Mentoraat was no longer organised by De Leidsche Flesch. De Leidsche Flesch was no more than a name.

In November 1973, a new board (by the use of a coup) was established by Jaap van der Wel, Wouter de Vries en Hans van Weeren. They discovered that the association was in an even worse state than expected. They wanted to organise a meeting with the members. After this announcement, six studente resubscribed for De Leidsche Flesch. The conclusion was to bring new life to De Leidsche Flesch. This succeeded. Students were still interested in lectures, excursions etc, apparently. In 1975, a new periodiek was published, “Leidscheflescht” (to be pronounced as “Leids flest”), still under the same board. In April of 1975, the trio was replaced by a new board, along with the still present “shadow board”.

At that moment, De Leidsche Flesch has members and enough activities coming. Mentoraat is brought back to the association. The subsets are probably lost, however. There are three publications of Leidscheflescht and between 1975 and 1982, no papers are found in the archive. In 1982, we find one piece of existence of the association: the plan of the new board for the next year. Apparently, there are still at most a few subsets. The board does introduce a change in the legislative acts, namely including computer science as one of the studies of De Leidsche Flesch. Moreover, we know that the students have moved to the Snellius and Huygens buildings and that the whole archive was in a container for a few hours. In 1988, there is a need for a new paper. The paper exists for a few more years, but is not directly related to De Leidsche Flesch. The paper does follow a paper that is property of De Leidsche Flesch, Amfora, but apparently this did not cover enough information for physics- and astronomy students. From 1994 to 2002, another paper is being published, Flesschepost and from 1997 to 2001/2002, the IMPACt, an independent paper in A4-format, brought out 4 times per year. In 2003, these two merge, resulting in Eureka!, which is still in existence.

During my own time at De Leidsche Flesch (since 2004), we had at a random moment a maximum of five subsets. Kaiser, for astronomy studente, was established in 1993 and is therefore our own still living subset. De Flesch van Klein, for mathematics, is established in 2001, but deceased unfortunately in 2006/2007. Moreover, there is the KLR, which was established in 2002 as a volleyball team, but transformed soon after in a subset. Enigma, for computer science students, was established in 2002, but stopped in 2005 and Nescia, finally, created in 2003, deceased in 2009. The greatest part of our members is not a member of a subset, but many are members of a committee. The board and the committees organise at least two activities per week during the whole year. De Leidsche Flesch participates in national initiatives and also organises them, like the Lieve Maria-actie in 2006. De Leidsche Flesch is very active and even more active year by year and I expect that is will be the case for a long time.

Source: the lecture given by Marcel van Daalen at the Alumni evening of August 2007.