自从美索不达米亚和埃及时代以来，玻璃就已经被制造出来了，它只不过是沙子、苏打灰和石灰的混合物。

Glass, which has been made since the time of the Mesopotamians and Egyptians, is little more than a mixture of sand, soda ash and lime.

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列入关注的理由： 默拉皮火山属于普林尼式喷发，大约每千年大规模爆发一次（喷涌而出的岩浆总量可达1立方千米，漫天飞扬的火山灰足有20至50千米高）。

Reasons to worry: Merapi is capable of producing a Plinian eruption (spewing at least 1 cubic kilometer of magma and producing 20 to 50 kilometer-high ash columns)every 1,000 years or so.

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图米说，喀斯特景观还受灰岩石开采的威胁。

Karst landscapes are also threatened by limestone quarrying, Toomey said.

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