Electrophysiologic approaches to the analysis of innervation in ocular motility have made evident the need for quantitative techniques.1 That need has now been satisfied with the development of a full wave integrator and differentiator in one instrument. The former provides an integration of the energy developed in specific time intervals. The height of the condenser discharge is exactly proportional to the energy accumulated and discharged within these intervals. This discharge is fed into a second beam of the dual beam oscilloscope or can be written out on an ink writer. A simple linear measurement gives the desired information. The frequency response is from 5 to 1000 cps—a spectrum deemed adequate for electromyographic potentials. The importance of this advance cannot be underestimated, since the evaluation of neuromuscular activity involves consideration of both amplitude and frequency. Inspection methods are inadequate to perform this task satisfactorily. In addition, the differentiator provides an