Chapple (1940) believed that the most important characteristic of an individual?s interaction could be measured along a dimension of action? silence. Using a machine that he called an , he conducted many studies that were based largely on recordings of the frequency and duration of speeches and silences. Social scientists and trainers who have followed in Chapple?s footsteps have concentrated on observing only the pattern of interaction (for example, who communicates, how often, how long and with whom?)