Quadrangle index
The quadrangular index ( Chinese 四角 號碼 / 四角 号码 , Pinyin sìjiǎo hàomǎ ) is a method of finding Chinese characters in reference books and also serves as one of the input systems for the Chinese writing . The four corners of the imaginary square, in which each character has to be placed, are designated with numbers. This method was invented in the 1920s by Wang Yunwu , the chief editor of Commercial Press Ltd., China; originally as an aid to the Chinese telegraph system. In the original European model, Morse code was sufficient to encode all the important elements of the Latin alphabet. The Chinese script, on the other hand, needed a different approach to convert the large number of characters into signals. Before the development of the four-corner system, Chinese telegrams were encrypted with a four-digit numerical code that had to be encrypted and decrypted using manuals. The four-corner method was the first attempt to develop a systematized code.
According to this method, a character is divided into four sectors, the order of which is always arranged as follows:
- top left
- top right
- bottom left
- bottom right
Each sector is then assigned a number from 0 to 9, which represents the dominant stroke sequence:
- 1 横héng ("horizontal") = 一 horizontal line
- 2 垂chuí (“vertical”) = 丨 vertical or 丿 diagonal line
- 3 点diǎn ("point") = 丶 point
- 4 叉chā ("crossing") = 十 cross made of one line
- 5 插chā (“peg, plug”) = 廾 two or more crossed lines
- 6 方框fāngkuàng ("square") = 口 rectangle
- 7 角jiǎo ("corner") = 厂 angle
- 8 八bā ("eight") = 八 two separate strokes
- 9 小xiǎo ("small") = 小 three separate lines
- 0 头tóu ("head") = 亠 line with a point or repetition of the bar code in the adjacent sector
Examples in the graphic:
- 聂niè (a Chinese surname): 1044
- 回huí ("to return"): 6060
- 哦ò ("oh"): 6305
- 甘gān ("sweet"): 4477
There is a memorable poem to help you learn the 10 categories:
In traditional characters:
橫 一 垂 二 三點 捺 ，
叉 四 插 五 方框 六 ；
七 角 八 八九 是 小 小
點 下 下 有 橫 變 零頭。
In abbreviations:
垂一二三点捺横
叉四五插方框六
七角八八九是小
点下有变横零头
Rough translation for German speakers:
With one across, with two lengthways, with three a spot,
four paths an intersection, five paths double,
six sides have a box, seven points need a corner,
through eight in two, with nine in three, with nothing point and line.