Measuring tower - A drawing of a tall tower with a clock on it
Summary
Qin Jiushao diagram for Observing pagaoda
中文(简体): 数书九章 望塔图
Date
1247
Source
mybook 唐戈藏书
Copyright info
public domain
Summary
Qin Jiushao diagram for Observing pagaoda
中文(简体): 数书九章 望塔图
Date
Source
Copyright info