Deltar
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/97/De_Deltar%2C_27_januari_1972.jpg/220px-De_Deltar%2C_27_januari_1972.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Beschrijving_van_de_Deltar.jpg/220px-Beschrijving_van_de_Deltar.jpg)
The Deltar (Delta Getij Analogon Rekenmachine, Dutch for Delta Tide Analog Calculator) was an analog computer, used from 1960 until 1984 in the design and implementation of the Delta Works.
The computer was designed and built in order to make the complicated calculations required to predict the effects of dams, dikes, and storm surge barriers on the tides in the estuaries of the rivers Rhine, Meuse and Scheldt.
The design of the Deltar was based on the analogy that exists between the properties and behaviour of water and electricity. Working with analogs of quantities such as water's height, rate of flow, and water storage, the design for the calculator basically used the electrical quantities charge, potential, inductance and capacitance.