y emotional are nearly identical among men from
physiological causes which do not affect with the same similarity
the processes of thought. The large number of corporeal gestures
expressing intellectual operations require and admit of more variety
and conventionality. Thus the features and the body among all mankind
act almost uniformly in exhibiting fear, grief, surprise, and shame,
but all objective conceptions are varied and variously portrayed. Even
such simple indications as those for "no" and "yes" appear in several
differing motions. While, therefore, the terms sign language and
gesture speech necessarily include and suppose facial expression when
emotions are in question, they refer more particularly to corporeal
motions and attitudes. For this reason much of the valuable
contribution of DARWIN in his _Expression of the Emotions in Man and
Animals_ is not directly applicable to sign language. His analysis
of emotional gestures into those explained on the principles of
serviceable associated habits, of antithesis, and of the constitution
of the nervous system, should, nevertheless, always be remembered.
Even if it does not strictly embrace the class of gestures which
form the subject of this paper, and which often have an immediate
pantomimic origin, the earliest gestures were doubtless instinctive
and generally emotional, preceding pictorial, metaphoric, and, still
subsequent, conventional gestures even, as, according to DARWIN's
cogent reasoning, they preceded articulate speech.

While the distinction above made between the realm of facial play and
that of motions of the body, especially those of the arms and hands,
is sufficiently correct for use in discussion, it must be admitted
that the features do express intellect as well as emotion. The
well-known saying of Charles Lamb that "jokes came in with the
candles" is in point, but the most remarkable example of conveying
detailed information without the use of sounds, hands, or arms,
is given by the late President T.H. Gallaudet, the distinguished
instructor of deaf-mutes, which, to be intelligible, requires to be
quoted at length:

"One day, our distinguished and lamented historical painter, Col. John
Trumbull, was in my school-room during the hours of instruction, and,
on my alluding to the tact which the pupil referred to had of reading
my face, he expressed a wish to see it tried. I requested him to
select any event in Greek, Roman, English, or American h