Abstract
It is a point in dispute whether “Shinsou-Senjimon”, which is one of ancient manuscripts written by writing-brushes, is a work that was written originally or a traced one. On the other hand, it is clearly handed down that “Souranjo” was written by “toumo” which was one of unknown skilled techniques for copying. In this paper, we compare several characters from these two ancient manuscripts by writing-brushes from viewpoints of the distribution of gray values and their gradient in the direction of making strokes by writing-brush. It is observed from the result of comparison that in the case of characters in Sinsou-Senjimon the difference in gray values of pixels in each character is large compared with that in the Souranjo.