The Quadoo Alphabet (the Quadoo Writing) as square braille or square writing for the blind (also called line alphabet, square script or
square scripture) was developed for handwritten notes
by the blind. In this case, a hole slate is used with square
holes and written only with six lines side correctly.
Quadoo is a relief writing and as a curveless blind
handwriting also an alternative for touch and / or learning
impaired blind. Other blind people can use this for quick notes
too. The Quadoo Alphabet can also be used outdoor as a makeshift
writing. Because only vertical, horizontal and diagonal lines form the characters.
---------- Quadoo Alphabet: ----------
Only the four sidelines of a square and the two
diagonals are used. To describe the lines, the
four corner points are numbered as follows:
top: [1] [2]
bottom: [3] [4]
or the following abbreviations are used for the letter code:
t = top, b = bottom,
r = right, l = left,
u = up, d = down
For each character the points are to
be connected in the following order:
A = 3-2-4 = ru
B = 1-2-4-3-2 = trbu
C = 4-3-2 = bu
D = 3-2-4-3 = rbu
E = 2-1-3-4 = tbl
F = 2-1-3 = tl
G = 2-1-4 = td
H = 1-3 + 2-4 = rl
I = 3-2 = u
J = 2-4-3 = rb
K = 1-3-4-3-2 = blu
L = 1-3-4 = bl
M = 4-2-1-3-2 = trlu
N = 3-1-4-2 = rld
O = 2-1-3-4-2 = trbl
P = 3-1-2-3 = tlu
Q = 1-2-4-3-1-4 = trbld
R = 3-1-2-1-4 = tld
S = 3-4-1 = bd
T = 1-2-4 = tr
U = 1-3-4-2 = rbl
V = 1-3-2 = lu
W = 1-3-4-2-3 = rblu
X = 1-4 + 2-3 = ud
Y = 2-4-3-4-1 = rbd
Z = 1-2-3-4 = tbu
1 = 2-4 = r
2 = 1-2-4-3 = trb
3 = 1-2-4-2-3 = tru
4 = 4-1-2-3 = tsd
5 = 2-1-4-3 = tbd
6 = 2-1-3-4-1 = tbld
7 = 1-2-3 = tu
8 = 2-1-4-3-2-1 = tbud
9 = 3-4-2-1-4 = trbd
0 = 2-1-3-4-2-3 = trbluto the top
- the Quadoo Alphabet as text version
including punctuation
For the Quadoo Alphabet, only the sides and diagonals of a square are
used (two lines horizontally, two vertically and two diagonally) which
makes it very easy to write with a stencil. There are no
circles or arcs in the letters and numbers that the blind can only
write inaccurately, only the punctuation marks contain dots.
And best of all: Quadoo contains clearly defined numbers.
All characters are derived from the black text, which
gives a high re-recognition effect and makes
it easier to read optically than Moon. If the
size is right, Quadoo will feel good too.
A similar alphabet like Qadoo with lines and dots had already been proposed in
1670 by the Italian Francesco Lana di Terzi, but his alphabet
was intended from the outset for the blind to hide secrets:
Helen Keller and her square script
Helen Keller used a square font other than Quadoo,
in which the letters were written very square.
Here first write attempts from 1887:
The most difficult point in this writing is the question mark, because
it should be detectable without confusion and must also
satisfy tactile as well as optical requirements.
In the course of development different question marks were tested,
but different requirements depending on the representation,
the tactile and optical readability of the text and the
restriction to the square of 6 lines and 5 dots,
no variant is to be regarded as optimal.
The last choice fell on the unused character lines ,
where a dot expansion was possible and which
tactile is well detectable. In some representations of the alphabet is deviated from it.