The principle just discussed,—that key depends on the degree of tension, first mental, then physical,—is of very wide application. As a matter of fact, it explains the whole subject of melody. In passing from a controlled to a less controlled state, the voice rises, and vice versa. To illustrate: Brutus says to Cassius, “You yourself are much condemned to have an itching palm”; and Cassius replies, “I an itching palm!” On the word “I” the voice of Cassius strikes upward through, perhaps, an octave of the scale, and this inflection manifests the increasing tension of Cassius’ mind as he utters the exclamation. It is almost impossible to restrain the tension of throat and hand while reading the passage. Note how the muscular tension increases while one is speaking the words of Cassius. Bearing in mind what has been said of the relation of bodily tension to pitch, the explanation of Cassius’ inflection will not be far to seek. Again, Brutus says, “The name of Cassius honors this corruption, and chastisement doth therefore hide his head.” Cassius replies in one word, “Chastisement.” There are two interpretations of this word: one, that Cassius replies, as if questioning, “Do you dare say this to me?” and the other, that, astounded at the bluntness of Brutus’s speech, Cassius replies, speaking to himself, “He dared speak of chastisement to me!” In the first case the inflection would be rising, denoting the increase of tension; in the second case, the inflection would be falling, marking a gradual decrease of tension. Let the reader experiment on this example, and observe how the mental tension corresponds with the physical tension.
The melody in which any phrase or sentence is given consists of a series of waves, the crests of which mark the maximum of tension. It is a difficult matter to indicate speech melody, but it is hoped the following illustrations will be at least sufficiently suggestive to make clear the psychology of melody. In the following sentence there is a gradual ascent of the voice, since the intensity increases from the first word to the end.
Came I not forth upon thy pledge my father’s hand to kiss?
Again, we have a very similar melody in this:
Would you wrest the wreath of fame
From the hand of fate?
The descending melody, denoting that the maximum of tension is at the beginning of the sentence, is found in the following:
All gloom, all silence, all despair!