Museum Boerhaave – 1930 Wiess electromagnet

Made by Siemens & Halske

It was the world second largest electromagnet.

From their website:

National Museum of the History of Science and Medicine

As the national treasury of scientific endeavours, the museum shows some 400 years of advances in knowledge. Developments in the various sciences can be viewed in 24 rooms on two levels. The emphasis is on contributions from the Netherlands.