It wasn't until 1906 that a scholar came across the prayer book in a library and realized it was a palimpsest, and that the underlying layer of texts could only have come from Archimedes.

直到1906年，一位学者才在图书馆偶然发现了这本祈祷书，并意识到它是一本重写本，而且底层的文本只可能出自阿基米德之手。

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The development of successful data security strategies should not only focus on the underlying layer, but should try to cover all threats.

制定成功的数据安全策略不能仅仅着眼于基础层，而应该尽力覆盖所有威胁。

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The water evaporates and the salts are left behind, creating a white crustal layer that prevents air and water from reaching the underlying soil.

水蒸发留下盐分，形成白色的地壳层，阻止空气和水进入下面的土壤。

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More on the underlying layer in a bit.

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Get through that covering layer and the underlying slivery colour of the aluminium itself will show through the black layer.

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Essentially, they isolated a rectangular column from the surrounding snowpack and used a snow saw to start an artificial fracture by cutting through the weak underlying frost layer, then watched what happened.

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