These medieval numerals were developed by the Cistercian monks in the early 13th Century. They can represent any integer between 0 and 9999 with a single character. On a central stave, the marks for 1 to 9 are positioned in the 4 corners of the character to signify the place value, units, tens, hundreds and thousands. The stave was originally horizontal, but this vertical stave form was more prevelent from the 14th Century.