As the earliest unified feudal empires in Chinese history, the Qin and Han dynasties provided fertile ground for the development of geography with their political unity, sound policies, comprehensive administrative divisions, developed maritime and land transportation, and the prosperous mining and handicraft industries. During this period, the invention of papermaking not only spurred on the dissemination of geographical knowledge, but map-making and the compilation of geographical chronicles also flourished. The emergence of primitive meteorological and geographical instruments marked a new level of understanding of the Earth's morphology and natural phenomena. Moreover, the geographical thinking and concepts which appeared in the Weishu, along with the ideas about environmental protection and policies, reflected these societies’ concern for nature at that time. The Qin and Han people also made significant progress in the study and understanding of minerals and rocks.