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Louis Braille's original publication, ''Procedure for Writing Words, Music, and Plainsong in Dots'' (1829),〔(''Procédé pour écrire les Paroles, la Musique, et le Plain-chant au moyen de points'' )〕 credits Barbier's night writing as being the basis for the braille script. It differed in a fundamental way from modern braille: It contained nine decades (series) of characters rather than the modern five, utilizing dashes as well as dots. Braille recognized, however, that the dashes were problematic, being difficult to distinguish from the dots in practice, and those characters were abandoned in the second edition of the book. The first four decades indicated the 40 letters of the alphabet (39 letters of the French alphabet, plus English ''w''); the fifth the digits; the sixth punctuation; the seventh and part of the eighth mathematical symbols. The seventh decade was also used for musical notes. Most of the remaining characters were unassigned. ==Script== As in modern braille, most of the higher decades were derived from the first: *Decades 1–4 were the same as today and had their modern French values. *Decade 5 was not derived from the first. (See image at left or table below.) Like the first decade, only the top half of the cell was used.〔In the image, digits 9 and 0 appear shifted downward. However, the verbal description clarifies that they also occupy the top half of the cell.〕 The digit 1 was a dash in the top row; 2 was dashes in the top and mid rows. (That is, these were ''a'' and ''b'', or modern digits ''1'' and ''2'', but with dashes in place of dots.) 3–5 were a top dash with a left, double, and right dot in the middle; 6–8 were a mid dash with a left, double, and right dot at top. 9 and 0 were ''a'' and ''b'' shifted to the right (that is, the modern French superscript and currency signs, and ): 175px *Decade 6 was derived from the first by adding dash at the bottom. That is, it resembled the 3rd decade with the two bottom dots connected into a line. *Decade 7 was formed with a dash in the top row of the cell, displacing the dots of the first decade downward. That is, it was much like the modern fifth decade with an overstruck dash at the top. For the 1st and 3rd characters of the decade, however, the dots were shifted all the way down to the bottom row, rather than shifted once to the middle as in the modern 5th decade: No character outside the original 1st and 5th decades occupied just the top half of the cell. *Decade 8 was formed by ''splitting'' the first decade with a dash, placing it between the upper and lower parts of each sign.〔Braille conceived of his script as being based on a 4-dote, 2×2 square supplemented with additional dots and dashes. Thus the middle row is the lower part of the basic sign, and the bottom row is below the basic sign; thus the letter ''b'' has a dot in "each" position of the left-hand column, while the letter ''l'' has an additional dot "below" the column.〕 That is, a dash appeared in the middle row, displacing the dots of that row to the bottom of the cell. In the case of first and 3rd characters (from ''a'' and ''c''), which did not have dots in the middle row, the dots at the top were displaced to the bottom instead. That is, this decade was equivalent to adding an overstrike to . *Decade 9 was derived from the fifth (the digits) by adding a dash in the bottom row. These were left unassigned apart from the first three, which were used when needed as markers of words, music, and plainsong, respectively. Thus the 1st and 5th decades occupied only the top half of the cell, while all characters in the other decades had a dot or dash in the bottom row. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1829 braille」の詳細全文を読む スポンサード リンク
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