The paper commences with the equation derived in 1853 by Kelvin, for circuits containing inductance, resistance and capacitance. From this, the history of a graphical analysis is traced from Sumpner in 1888, to Drysdale who in 1910 published details of his planimeter, a manual device to solveLRandCRcircuits. Little was added to the method, until Marchant extended it, in 1960, to cover all three circuit parameters,L,RandC, by one graphical solution. The methods are useful in explaining circuit operation and examples of use are given.