there
is the added complication of drum-taps of unequal force, the element of
comparative stress must be reckoned with. And if, finally, the drum-taps
are not in the same key (say, on kettledrums differently tuned), then
the further element of comparative pitch must be considered as a
possible point of emphasis. In a word, pitch may sometimes be
substituted for stress.

In music rhythmic units may be marked by differences in tone-quality as
well, and thus the potential complexity is greatly increased; but in
spoken language, as has been said, this element of rhythm is
negligible. In speech-rhythm, however, the three conditions of time,
stress, and pitch are always present, and therefore no consideration of
either prose rhythm or verse can hope to be complete or adequate which
neglects any one of them or the possibilities of their permutations and
combinations. And it is precisely here that many treatments of the
rhythm of language have revealed their weakness: they have excluded
pitch usually, and often either stress or time. They have tried to build
up a whole system of prosody sometimes on a foundation of stress alone,
sometimes of time alone. The reason for this failure is simple, and it
is also a warning. Any attempt to reckon with these three forces, each
of which is extremely variable, not only among different individuals but
in the same person at different times--any attempt to analyze these
elements and observe, as well, their mutual influences and combined
effects, is bound to result in a complication of details that almost
defies expression or comprehension. The danger is as great as the
difficulty. But nothing can ever be gained by the sort of simplification
which disregards existent and relevant facts. It is to be confessed at
once, however, that one cannot hope to answer in any really adequate way
all or even most of the questions that arise. The best that can be
expected is a thorough recognition of the complexity, together with some
recognition of the component difficulties.

Moreover, only a part of the problem has been stated thus far. Not only
is all spoken language the resultant of the subjectively variable
forces of time, stress, and pitch, but these three forces are themselves
subject to and intimately affected by the thought and emotion which they
express. Though educated persons probably receive the phenomena of
language more frequently through the eye than through the ear, it is
true that word