[§ 673]. Convertible metres.—Such a line as—
Ere her faithless sons betray'd her,
may be read in two ways. We may either lay full stress upon the word ere, and read—
Ére her faíthless sóns betráy'd her;
or we may lay little or no stress upon either ere or her, reserving the full accentuation for the syllable faith- in faithless, in which case the reading would be
Ere her faíthless sóns betráy'd her.
Lines of this sort may be called examples of convertible metres, since by changing the accent a dissyllabic line may be converted into one partially trisyllabic, and vice versâ.
This property of convertibility is explained by the fact of accentuation being a relative quality. In the example before us ere is sufficiently strongly accented to stand in contrast to her, but it is not sufficiently strongly accented to stand upon a par with the faith- in faithless if decidedly pronounced.
The real character of convertible lines is determined from the character of the lines with which they are associated.