The North Sea Flood occurred on the evening of the 31 January 1953 when low atmospheric pressure, high winds and a high spring tide caused the sea level to rise five metres above its usual height. Serious flooding occurred on the east coast of England, the Netherlands, and Belgium.  To perform his analysis, Ishiguro constructed an analog computer which relies on the mathematical similarity between the flow of electricity through a network and the flow of water in the sea during a storm-surge. The storm surge computer is now on display in the Mathematics: the Winton Gallery of the Science Museum in London as part of an exhibit about mathematical modelling of the sea.