Abstract
A high gain D.C. amplifier, with feedback capacitor and input resistor, can integrate any voltage present at its input, with respect to time and it overcomes many short-comings of a simple R.C. network integrator. The presence of such an integrator in an analogue computer makes it possible to solve differential equations in a straightforward manner. In the present paper the operation of the integrator is discussed and the way of solving differential equations is illustrated through two examples.