"Lorentz, Lely, Thijsse and the Afsluitdijk"

Dear members of the KIVI Department of History of Technology and of Histechnica,

The announced lecture and guided tour at the Maritime Museum Rotterdam, with the exhibition "Te Water: Discover Dutch Shipbuilding" can unfortunately cannot take place take place.

The Science Centre has indicated that the hall will not be available on the planned Saturday 27 September due to renovation, therefore we will now meet on Saturday 20 September.

however, the boards of the association Histechnica and of the KIVI section History of Technology are pleased to invite you to attend a lecture to be given by Mr Ir. F.W. van den Berg with the title:

"Lorentz, Lely, Thijsse and the Afsluitdijk"

Programme:

  • 10.30 am: Walk-in with coffee and tea
  • 11:00: Welcome and introduction
  • 11.05:00: Lecture by Mr Frank van den Berg
  • 12:00: Break
  • 12:15: Continuation of lecture and closing discussion
  • 12:45: End of meeting

Summary of the lecture .

It took more than 40 years to realise the plans for the Afsluitdijk, from 1891 to 1932. Dr Ir Cornelis Lely was the inspiration, after many preliminary plans. There was much opposition to it. After the "minor" flood of 1916, progress was made through the work of a State Commission (1918 - 1926) led by Nobel laureate Prof Dr Hendrik Lorentz, then the scientific "curator" of the Teylers Foundation in Haarlem. His right-hand man in this was Bloemendaler (later Prof Dr) Ir Jo Thijsse (son of biologist Dr Jac. P. Thijsse). Lorentz and Thijsse developed complex mathematical models of the current profiles in the Wadden Sea. As a result, the course of the Afsluitdijk was modified. Thijsse later became a professor in Delft and was the founder of the Waterloopkundig Laboratorium.

Information about the speaker

Ir. Frank W. van den Berg (Haarlem) talks about all these plans and the special lives of the three protagonists involved. He is chairman of the "History of Technology" section of KIVI and a tour guide at Teylers Museum. After grammar school Ɵ in Rotterdam, he studied Mechanical Engineering at TU Delft and Economics (MBA) at Columbia University (NYC). He pursued a business career, partly abroad (13 years), partly as an entrepreneur. He was also part-time attached to VU University as an associate professor of Financial Risk Management and Entrepreneurship and active in regional politics for 14 years (member of Provincial Council NH and City Council).

Upcoming activities at Science Centre Delft:

  • Saturday 25 October 2025 at 11:00 am lecture by Dr H. Ekkelenkamp: "The origins of Geodetic Heritage in the Netherlands and the former Dutch East Indies".
  • Saturday 22 November 2025 at 11:00 a.m. lecture by Ir. R.J. de Heer: "Nine Centuries of Hydraulic Engineering as an Export Product".
  • Saturday 20 December 2025 at 11:00 a.m. lecture by Ir. G.J. Luijendijk: "The Gliding Bridge across the World".

On the occasion of Histechnica's 50th anniversary, a book "Uit Falen Vooruitgang Halen" was published on Saturday 20 April 2024. The book will be available free of charge during the lecture