巢元方：诸病源候论·第2324则

九卿退就位立。禮部太常寺官奏耕籍禮畢。導駕詣齋宮。教坊司作《導迎大樂》、至齋宮門、樂止。宮內大樂作上陞座。樂止。王以下文武陪祀各官、入東西兩旁門。分翼排立。鴻臚寺官贊「跪、叩頭。」順天府官率兩縣官併耆老人等、行三跪九叩頭禮。農夫三十人隨後行。禮畢、府縣官從西門出，率農夫至耕籍所終畝。賜王、貝勒、貝子、公坐。候耕畢。府縣官從東門入。《鴻臚》寺官贊排班。王等於臺上、文武各官於臺下、俱排立。鴻臚寺官於齋宮門外東旁、西向跪。奏親耕既成、禮當慶…

上密問太史令李淳風：「《秘記》所云，信有之乎？」對曰：「臣仰稽天象，俯察歷數，其人已在陛下宮中，為親屬，自今不過三十年，當王天下，殺唐子孫殆盡，其兆既成矣。」上曰：「疑似者盡殺之，何如？」對曰：「天之所命，人不能違也。王者不死，徒多殺無辜。且自今以往三十年，其人已老，庶幾頗有慈心，為禍或淺。今借使得而殺之，天或生壯者肆其怨毒，恐陛下子孫，無遺類矣。」上乃止。

It is hardly believable that for several years we were able to dispose of the highly phosphoric cinder from the puddling furnaces at a higher price than we had to pay for the pure cinder from the heating furnaces of our…