A rather rare Feng Shui Ruler also known as a Rui Ban Ruler.
It was initally designed and institutionalized by Rui Ban Jing who was the most famous carpenter and architect in ancient times.He pionered the use of Feng Shui in building. This method of measurement which has been used by Feng Shui masters since.
This and the Feng Shui Compass are the most important tools that were in use.
The Feng Shui foot is 43 cms (approximately 17 inches). The Feng Shui foot was derived from the side of a square, where the length of the diagonal of a square is the square root of two. Western mathematicians called this the "Magic Square" and this was considered by the Chinese as "mystical". This is almost identical to the standard imperial foot which was developed much later.
The ruler is made of bronze. All markings are clearly visible. Solid and excellent condition except for some minor denting at one end on the overhang portion which has not scarred or distorted the markings.