清·李光地 等奉敕撰 · Chapter 186 / 273
三伏
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Chapter 186 of 273
厯例曰三伏者四时代谢皆以相生立春以木代水水生木也立夏以火代木木生火也立冬以水代金金生水也至于立秋以金代火金畏火尅故至庚日则必伏藏庚者金也金气伏藏则火益炽三阳数也故夏至后第三庚为初伏第四庚为中伏立秋后初庚为末伏谓之三伏如夏至日得庚便为初庚立秋日得庚亦即为末伏也
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