不知名的合金已经在古代的棕榈叶手稿透露出来。

Unknown alloys have been revealed in the ancient palm leaf manuscripts.

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写下的手稿在中世纪被用来教学，写在白桦树皮和棕榈叶上，直到16世纪出现印刷机为止。

While written manuscripts were used for teaching in medieval times, they were written on birch bark or palm leaves, until the advent of the printing press from the 16th century.

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