[1] `Naturgeschichte der Saugethiere von Paraguay,' 1830, s. 55.

[2] Mr. Tylor gives an account of the Cistercian gesture-language
in his `Early History of Mankind' (2nd edit. 1870, p. 40), and makes
some remarks on the principle of opposition in gestures.

[3] See on this subject Dr. W. R. Scott's interesting work, `The Deaf
and Dumb,' 2nd edit. 1870, p. 12. He says, "This contracting
of natural gestures into much shorter gestures than the natural
expression requires, is very common amongst the deaf and dumb.
This contracted gesture is frequently so shortened as nearly to lose
all semblance of the natural one, but to the deaf and dumb who use it,
it still has the force of the original expression."

Many signs, moreover, which plainly stand in opposition to each other,
appear to have had on both sides a significant origin.
This seems to hold good with the signs used by the deal and dumb
for light and darkness, for strength and weakness, &c. In a future
chapter I shall endeavour to show that the opposite gestures of
affirmation and negation, namely, vertically nodding and laterally
shaking the head, have both probably had a natural beginning.
The waving of the hand from right to left, which is used as a negative
by some savages, may have been invented in imitation of shaking the head;
but whether the opposite movement of waving the hand in a straight
line from the face, which is used in affirmation, has arisen through
antithesis or in some quite distinct manner, is doubtful.

If we now turn to the gestures which are innate or common to all