“Whitewashed walls” marked more than just a building. The 外井7号烽火台, or Waijing 7 Hao Fenghuotai, stands as a silent sentinel. It whispers tales of the Ming Dynasty’s early warning system. Let me tell you its story.
外井7号烽火台 once played a vital role. It stood as a beacon-equipped tower. These towers sent early warnings across the land. During the Ming Dynasty, specifically between 1567 and 1620, many such towers were constructed.
Qi Jiguang, a general, oversaw this large-scale construction. These weren’t just ordinary towers. They were beacon-equipped hollow enemy towers. This meant they served multiple purposes. They functioned as garrisons and storage. Surveillance was another key function. Of course, they were also used for firing weapons. But most importantly, they spread early warning signals.
How did they differ from standard towers? Look closely. Notice anything different? Beacon-equipped towers were whitewashed. Lime covered the crenelated and waist walls. This made them stand out. Even existing solid beacon towers received this whitewash treatment.
Historical documents confirm this practice. The “Practical Record of Military Training” notes that hollow enemy towers within 160 meters of a beacon tower would serve as the beacon tower. “Chronicles of Four Towns and Three Passes” adds that hollow enemy towers replaced insufficient solid beacon towers. These replacements received special markings. “Imperial Ming Legal Records” details the whitewashing process. Lime white marked the four sides of the crenelated wall and the waist wall. Solid beacon towers were also whitewashed to keep the markings consistent.
Archaeological analysis supports these records. Researchers have identified four hollow enemy towers along the Ming Ji Town Great Wall. They are Xuliukou No. 02, Xuliukou No. 03, Damaoshan No. 03, and Yumuling No. 06. These are remnants of beacon-equipped towers. Based on this, experts believe the remaining 49 hollow enemy towers with plaster remnants were also beacon-equipped.
Material analysis provides further evidence. XRD analysis reveals the plaster mortar mainly contains calcite, quartz, and dolomite. XRF results indicate a magnesium oxide content exceeding 5%. This categorizes the plaster as magnesian lime. It aligns with the mortar used in the tower’s interior brick joints.
Construction followed traditional practices. The “mud bottom lime” method was used. A mud mixture with straw formed the foundational layer. White lime plaster, mixed with hemp and other plant fibers, comprised the outermost layer.
Researchers have reconstructed the historical appearance. The whitewashed area covered the trapezoidal region between the crenelated walls and the arrow slit arches. Historical images, records, and artifacts aided this reconstruction.
外井7号烽火台 stands as a reminder. It echoes a time when signals flashed across the landscape. Now try to imagine soldiers on top. They are ready to light the signal fires. The smoke rises. It is a warning. The enemy is approaching.