The dye extracted from the indigo is bluer than the plant; so is the ice colder than the water.

青取之于蓝，而青于蓝；冰，水为之，而寒于冰。

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After coming up, put it in dye vat and dye stains, then boiled with water after dyeing well, finally display its "ice lines" after the wax melted.

绘成后，投入染缸渍染，染好捞出用清水煮沸，蜡溶化后即现出“冰纹”。

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You might start to think that staying at home would be the sensible thing to do, only this too is ridden with potential dangers for your unborn child: from ice-cream, to pet shampoo, to hair dye.

BBC: Pregnancy advice 'scaremongering'