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A resistance network analog is described which incorporates some improved features in flexibility, accuracy, and ease of operation. The network consists of 575 variable resistance units and is mounted on a 6‐ by 8‐foot board. The resistive units are of the plug‐in type, and the mesh size is smaller on one‐fourth of the board. The use of a control console, automatic digital voltmeter and numerous switches permits rapid measurement of voltages and currents. Improved equations are presented for calculating network resistances adjacent to the drain. These equations utilize a logarithmic expression rather than a linear one as reported by previous investigators. Comparisons are made of drain flow rates in homogeneous medium as evaluated by the network and by analytic solutions of Kirkham. Compared to the analytical solutions, the network data generally deviates < 2% if the logarithmic expression is used to calculate drain resistors; while deviations as high as 30% or more may occur if a linear relationship is utilized.