d their Language.

[Sidenote: SOUNDS UTTERED BY CHILDREN]

I shall take occasion here to mention some curious experiments, which
have suggested themselves to me in my work with the phonograph. For lack
of time and opportunity, I have not carried them far enough to give
exact and final results; but it has occurred to me that philology may be
aided by taking a record of the sounds made by a number of children
daily through a period of two or three years from birth. The few
experiments which I have tried in this particular line are sufficient to
show that the growth of speech obeys certain laws in the development of
vocal power. It is apparent to me that the first sounds uttered by
children have no consonants, and that certain consonants always appear
in a regular succession and always single. The double consonants develop
later, and the triple consonants appear to be the last acquirement. I
have not the space to go to great length on this subject, and my
experiments have not been sufficient to enable me to formulate with
certainty any set of rules by which the development of this faculty is
uniformly governed.

It is my purpose, on my return from Africa, to set on foot a series of
such experiments, with the hope of ascertaining the facts connected
therewith. And while in Africa I shall aim to make such records of the
natives as to ascertain whether their speech conforms to the same laws
of development or not. It is my earnest hope to be able to do the same
thing with the great apes which I am going chiefly to study. I think if
I can record on a phonograph cylinder the sounds uttered by a young
chimpanzee under certain conditions once each day for a year or so, I
can determine whether there is a like growth in their speech, and to
what extent the same laws control it. I have already observed that the
quality of voice in a given species of monkey changes with his age very
much in the same manner as the human voice; but I have not been able to
follow the changes through one individual specimen by which to ascertain
the exact manner of such change.

[Sidenote: SOUNDS OF BIRDS]

The sounds of birds have been studied perhaps more than any others
except those of man, but they have not been studied as speech, nor to
ascertain their meanings. Their musical character has attracted
attention and been the subject of some discussion. My opinion is that
much that has been said on that subject belongs more properly to the
realm