_MADAM,_
In answer to your question, What makes Eccho, I say, it is that which
makes all the effects of Nature, _viz._ self-moving matter; I know, the
common opinion is, that Eccho is made like as the figure of a Face, or
the like, in a Looking-glass, and that the Reverberation of sound is
like the Reflection of sight in a Looking-glass; But I am not of that
opinion, for both Eccho, and that which is called the Reflection in a
Looking-glass, are made by the self-moving matter, by way of patterning
and copying out. But then you will ask me, whether the glass takes the
copy of the face, or the face prints its copy on the glass, or whether
it be the _medium_ of light and air that makes it? I answer, although
many Learned men say, that as all perception, so also the seeing of
ones face in a Looking-glass, and Eccho, are made by impression and
reaction; yet I cannot in my simplicity conceive it, how bodies that
come not near, or touch each other, can make a figure by impression
and reaction: They say it proceeds from the motions of the _Medium_ of
light, or air, or both, _viz._ that the _Medium_ is like a long stick
with two ends, whereof one touches the object, the other the organ of
sense, and that one end of it moving, the other moves also at the same
point of Time, by which motions it may make many several figures; But
I cannot conceive, how this motion of pressing forward and backward
should make so many figures, wherein there is so much variety and
curiosity. But, say light and air are as one figure, and like as a
seal do print another body; I answer, if any thing could print, yet it
is not probable, that so soft and rare bodies as light and air, could
print such solid bodies as glass, nor could air by reverberation make
such a sound as Eccho. But mistake me not, for, _I do not say_, that
the Corporeal motions of light or air, cannot, or do not pencil, copie,
or pattern out any figure, for both light and air are very active in
such sorts of Motions, but I say, they cannot do it on any other bodies
but their own. But to cut off tedious and unnecessary disputes, I
return to the expressing of my own opinion, and believe, that the glass
in its own substance doth figure out the copy of the face, or the like,
and from that copy the sensitive motions in the eyes take another copy,
and so the rational from the sensitive; and in this manner is made both
rational and sensitive perception, sight and knowledg. The same with
Ecchoes; for the air patterns out the copy of the sound, and then the
sensitive corporeal motions in the ear pattern again this copy from
the air, and so do make the perception and sense of hearing. You may
ask me, _Madam_, if it be so, that the glass and the air copy out the
figure of the face and of sound, whether the Glass may be said to see
and the Air to speak? I answer, I cannot tell that; for though I say,
that the air repeats the words, and the glass represents the face, yet
I cannot guess what their perceptions are, onely this I may say, that
the air hath an elemental, and the glass a mineral, but not an animal
perception. But if these figures were made by the pressures of several
objects or parts, and by reaction, there could not be such variety as
there is, for they could but act by one sort of motion: Likewise is
it improbable, that sounds, words or voices, should like a company of
Wild-Geese fly in the air, and so enter into the ears of the hearers,
as they into their nests: Neither can I conceive, how in this manner
a word can enter so many ears, that is, be divided into every ear, and
yet strike every ear with an undivided vocal sound; You will say, as
a small fire doth heat and warm all those that stand by; for the heat
issues from the fire, as the light from the Sun. I answer, all what
issues and hath motion, hath a Body, and yet most learned men deny that
sound, light and heat have bodies: But if they grant of light that it
has a body, they say it moves and presses the air, and the air the eye,
and so of heat; which if so, then the air must not move to any other
motion but light, and onely to one sort of light, as the Suns light;
for if it did move in any other motion, it would disturb the light; for
if a Bird did but fly in the air, it would give all the region of air
another motion, and so put out, or alter the light, or at least disturb
it; and wind would make a great disturbance in it. Besides, if one body
did give another body motion, it must needs give it also substance, for
motion is either something or nothing, body or no body, substance or no
substance; if nothing, it cannot enter into another body; if something,
it must lessen the bulk of the body it quits, and increase the bulk
of the body it enters, and so the Sun and Fire with giving light and
heat, would become less, for they cannot both give and keep at once,
for this is as impossible, as for a man to give to another creature
his human Nature, and yet to keep it still. Wherefore my opinion is
for heat, that when many men stand round about a fire, and are heated
and warmed by it, the fire doth not give them any thing, nor do they
receive something from the fire, but the sensitive motions in their
bodies pattern out the object of the fires heat, and so they become
more or less hot according as their patterns are numerous or perfect;
And as for air, it patterns out the light of the Sun, and the sensitive
motions in the eyes of animals pattern out the light in the air. The
like for Ecchoes, or any other sound, and for the figures which are
presented in a Looking-glass. And thus millions of parts or creatures
may make patterns of one or more objects, and the objects neither
give nor loose any thing. And this I repeat here, that my meaning of
Perception may be the better understood, which is the desire of,
Madam,
_Your faithful Friend,_
_and Servant._