CJ Replay: Tactus

(An excerpt from the Choral Journal article, “Tempo and Mensural Proportion in the Music of the Sixteenth Century,” by Stephen A Kingsbury)

 

       At the most fundamental level, issues of mensuration and mensural proportion stem from the concept of tactus. Also referred to by theorists of the day as measure, full stroke, mensura, compas, misura, battuta, schlag, ictus, percussion, and prasescriptum, l the tactus was viewed as the unit of tempo. In a practical sense, the tactus was illustrated by an up and down movement of the hand, finger, or in the case of instrumentalists whose hands and fingers were engaged in the playing of theirinstruments, the foot.  In contrast to modern conducting gesture, neither the up movement nor the down movement was seen as possessing any rhythmic emphasis. Writers of the day even disagreed about the ordering of the movements; up before down, or down before up. Tactus was divided into two major types, depending upon the binary or ternary quality of the rhythm. In the context of modern conducting gesture, the binary tactus is the most straightforward. There is a clear correlation with a modern two-beat pattern; the up and down motions each having the same temporal duration. For a ternary tactus, the pattern remains the same except that one of the motions takes twice as long as the other; the result being a pattern that is three "clicks" in length.