In this paper, it is identified that the town planning for the tradesman class areas in the era of the japanese civil war had been operated by the geometrical and alzebraical method. The principal planning method for the south-east avenues in Echizen Ohno castle town was characterized by the techniques which divided the critical rectilinears into the 8 equal parts. "8" means lucky number. And, it is proved by the alzebraical method in this paper that the town planning in those days had been operated by the geometrical method and the precise surveying.
