The fontis were due to different causes : the friability of the soil ; some landslip at a depth beyond the reach of man ; the violent summer rains ; the incessant flooding of winter ; long , drizzling showers .

地陷有各种原因：土壤的易碎性；在人力所不能及的地下出现的崩塌；夏季的暴雨；冬季连绵不断的雨水；长期的毛毛雨。