According to art historian Patricia Simons, the plumb line "is a pendulous instrument that sways rhythmically but finds the true vertical, and a carnival song likened it to a cleansing plunger that removes 'grease.' … The obvious bulge in the satyr mason's apron is both a satirical comment on censorship and an example of how arousal was frequently displaced visually onto the bestial … "—The Sex of Men in Premodern Europe (Cambridge University Press, 2011), p. 19.