y deficient. They are not quite
devoid of vocal language, though it is doubtful if any of the sounds
made by them have a much higher linguistic office than that of the
interjection. But emotional sounds, to which these belong, are not
destitute of value in conveying intelligence. They embrace cries of
warning, appeals to affection, demands for help, calls for food
supplies, threats, and other indications of passion, fear, or feeling.
And the significance of these vocal sounds to animals may often be
higher than we suppose. That is, they may not be limited to the vague
character of the interjection, but may occasionally convey a specific
meaning, indicative of some object or some action. In other words, they
may advance from the interjection toward the noun or the verb, and
approach in value the verbal root, a sound which embraces a complete
proposition. Thus a cry of warning may be so modulated as to indicate to
the hearer, "Beware, a lion is coming!" or to convey some other specific
warning. We know that accent or tone plays a great part in Chinese
speech, the most primitive of existing forms, a variation in tone quite
changing the meaning of words. The same may be the case with the sounds
uttered by animals to a much greater extent than we suppose.

We know this to be the case with some of the birds. The common fowl of
our poultry yards has a variety of distinct calls, each understood by
its mates, while special modulations of some call or cry are not
uncommon among birds. The mammalia are not fluent in vocal powers,
their range of tones being limited, yet they certainly convey definite
information to one another. Recent observers have come to the conclusion
that the apes do, to a certain extent, talk with one another. The
experiments to prove this have not been very satisfactory, yet they seem
to indicate that the woodland cries of the apes possess a certain range
of definite meaning.

We are utterly ignorant of what powers of speech the man-ape possessed.
It must, in its developed state as a land-dwelling, wandering, and
hunting biped, have needed a wider range of utterance than during its
arboreal residence. It was exposed to new dangers, new exigencies of
life affected it, and its old cries very probably gained new meanings,
or new cries were developed to meet new perils or conditions. In this
way a few root words may have been gained, rising above the value of the
interjection, and expressing some degree of defi