Nomograms have been devised to aid in rapid calculation of body surface, basal metabolism rate, etc. (Geigy, 1962). Lindsley (1968) has also suggested their use in education. Figures 14.1 and 14.2 show two nomograms for obtaining rapid approximation of response rate. The right vertical axis is graduated along a time dimension, while the left axis is in a frequency dimension. When a straight edge is aligned across given values of time and frequency, the value on the diagonal at the point of intersection with the straight edge is the corresponding rate (frequency per unit time).