miscellaneous

From: Abraham Nemeth 356-5353 (anemeth@ece.eng.wayne.edu)
Date: Wed Nov 30 1994 - 09:39:13 PST


November 30, 1994

Hello to everyone from Dr. Nemeth:

     Robert Jaquiss' experiment with his capsule paper and soldering
iron reminds me of the comedian, Jose Jimenez, sometimes seeen on
TV and heard on radio. He speaks with a sing-song Hispanic accent.
His friend says to him: "I hear you have a big ranch."

     "I am very big ranchero, senor," replies Mr. Jimenez.

     "Tell us how many head of cattle you own," says his friend.

     "Very few, senor. Not many survived the branding."

     I would like to relate my experience with APH about the
raised-line drawings of the numbers and the various alphabets in
the Nemeth Code. I took ?it for granted that the largest braille
publisher in the United States (if not the world) would surely have
access to the various alphabets and could insert them into the
Code at the places I designated. Not so. They had no facility for
getting those alphabets, but they could enlarge them and
reproduce them in tactile form if I would send them a photocopy.
I remember going to the library with a sighted reader and my
Optacon to do a little research. When my sighted reader found a
collection of the alphabets I wanted, I would examine them with
my Optacon. After examining five or six such sets, I chose the
one that "looked" the best to me. I knew beforehand what all of
those letters should look like. I had them photocopied and sent
the copies to APH. The rest is history -- they got duly
incorporated into the Nemeth codebook. The alphabets included the
upper and lower case forms of all the letters in the English
alphabet, showing the customary, sanserif and script forms of these
letters. Except for sanserif, it also listed the same collection
of Greek, Gothic (German) and Cyrillic (Russian) letters. It also
included the printed and script forms of the Hebrew letters which
have no uppercase forms. All of these letters have a use somewhere
in mathematical or scientific notation. Not only does the
codebook show all these letters, but it also shows all the
symbols that each section deals with. Thus, in the section that
deals with signs of comparison, there are raised-line depictions
of the signs for equals, less than, greater than, etc.
Similarly, there are depictions of all the math operators in the
section that deals with operators, etc+. This should make a good
start on the kind of reference that Judy wants and which I think
is a good idea. But it is only a start; there are many many more
characters to depict in raised-line form than are included in the
Nemeth codebook.

     The sense of touch and the sense of sight are two very distinct
modalities. The sense of sight (together with the sense of hearing)
process distant events; the sense of touch can process only events
that occur within an arm's length. For the sense of touch, there
is no such thing as parallax, no light and shaded areas. But there
are textures that give the sense of touch a great deal of information.
The sense of touch is also intimately connected with the
kinesthetic sense, sometimes referred to as proprioception by the
higher-paid professors. It is this sense, and not the sense of
touch, that tells you how large an object is, what its shape is,
how it is oriented with relation to your body, how rigid it is,
etc.

     If I were to rely solely on my sense of touch, a perspective
drawing intended to represent a three-dimensional object would have
no meaning for me. But since I am familiar with drawing conventions,
I can synthesize that tactile drawing in my mind's eye taking
into account the drawing conventions that I know about; and there,
in my mind's eye, I can experience the three-dimensionality of the
drawing. In my teaching days, I have routinely drawn figures using
the drawing conventions I know to produce what my students perceived
as three-dimensional figures. For example, to draw a cone, you
first draw an elongated elipse (not a circle) to represent its
base. Then, by means of a dotted or dashed line along the long
axis of the ellipse, you create the illusion of seeing both the
"front" and the "back" of the base of the cone. The sides of the
cone are represented by two tall wedge-shaped triangles with the
points of the wedges at the vertex of the cone and the bases of the
triangle (very small) at each end of the ellipse. Again, if you
can manage to make the lines that form the inside of the wedge
finer than those that form the outside, you reenforce the illusion
that you can see both the front and the rear of the cone. It is
as if the cone were made of a solid piece of transparent
plexiglass where the aberation of light coincides with the wedges
you have drawn. I have no idea whether I make any sense, but
shouting about how to make a three-dimensional drawing is even
less effective than a tactile one. So I will leave off from
drawing here.

     You may have no doubt heard of many amputees who experience
a phantom itch in the big toe of their amputated foot. Although
the foot is gone, the rest of the neural mechanism is still there.
In my case, my eyes -- the interface to the outside world -- are
non-functioning, but the remaining visual apparatus, of which there
is a lot, is evidently still functional.

     For a non-practical treatise on how to make tactile drawings,
this posting is long enough, so I'll say so long for now.

anemeth@ece.eng.wayne.edu

 



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