Fig. 13 Relation of amplitude of pulsations of temporal artery to intensity of headache after administration of ergotamine tartrate. The sharp decrease in the amplitude of pulsation following injection of ergotamine closely paralleled the rapid decrease in intensity of headache. Representative sections of photographic record are inserted. The average amplitude of pulsations for any given minute before and after administration of ergotamine was ascertained by measuring individual pulsations from the photographic record. The points on the heavy black line (lower half) represent these averages, expressed as percentages. Initial or “control” amplitude was taken as 100%. (Dalessio DJ: Wolff's Headache and Other Head Pain, 3rd ed. New York: Oxford University Press, 1972)