Guarding secrets of the Ming Dynasty is \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0. It stands as a sentinel along the Yanqing Great Wall. This section of the wall saw reconstruction in the early Ming Dynasty. That was from 1368 AD to 1644 AD. Some believe it was built upon an even older stretch.
Now look closely at \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0. Notice anything different? During the Longqing and Wanli periods from 1567 to 1620, General Qi Jiguang supervised the construction of hollow enemy towers. This tower served multiple purposes. Garrisoning troops storing supplies surveillance and weapon firing all happened here. \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0 also functioned as a beacon tower.
Beacon-equipped hollow enemy towers helped to disseminate early warnings. How could they be recognized? They were whitewashed with lime on the crenelated walls. The waist walls on each of the four sides were also whitewashed. Even pre-existing solid beacon towers received this whitewash treatment.
Extensive research identified four hollow enemy towers as beacon-equipped remnants. \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0 might be one of the 49 remaining hollow enemy towers with plaster remnants. These remnants suggest they were beacon-equipped. These towers are primarily located in contemporary Hebei Province.
Let’s delve into the materials used to build \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0. XRD analysis reveals that the plaster mortar mainly consists of calcite quartz and dolomite. XRF results indicate a magnesium oxide content exceeding 5%. This classifies the plaster as magnesian lime. The exterior plaster and interior joint mortar likely came from the same materials and processes.
Field investigations shed light on the construction practices. The “mud bottom lime” technique was employed. This involved applying a mud mixture with straw as a foundation. White lime plaster mixed with hemp fiber formed the outermost layer.
Imagine the meticulous work required to plaster \u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0. The trapezoidal region between the crenelated walls and arrow slit vaults received plaster. Historical images and records aided in reconstructing the tower’s appearance.
\u5ef6\u5e86\u53bf 69 \u53f7\u654c\u53f0 stands as a testament to Ming Dynasty ingenuity. It blends defensive and communication functions. Its whitewashed walls once signaled warnings across the land. Today it whispers stories of soldiers builders and ancient strategies.