The timer was also used as an instrument/tool while firing ordinance. By watching down-range, and knowing the muzzle velocity of the ordinance being fired, accurate distance and site adjustment can be calculated based on elapsed time determined to within fractions of a second.
Xian Zhongnan Mountain | Trips to Mount Zhongnanshan | What to see in Xian
Where is The Zhongnan Mountains？ The Zhongnan Mountains are of the birthplaces of Taoism and are also called Taiyi Mountains. Situated 9.3 miles (15 km) to the south of Chang’an District in Xian City, these mountains form the middle section of the Qinling Mountains.