The discussion on symbolic operators in differential equations in recent numbers of the Gazette shows the need of a different method of attacking the linear equation of the second order with constant coefficients, which is the case most wanted in practice. It seems a pity that no method is given in the English books except the symbolic one, in which pass students get lost owing to their not understanding exactly what they can or cannot do with the operators. And is this to be wondered at when a theorem which gives erroneous results if not interpreted in a particular way has stood in Forsyth’s Treatise for forty years?