Detailed text transcripts for TV channel - DW - 20180412:07:52:00
Ago volcanic eruptions supplied the romans with an abundance of building materials tough limestone and pots of money catch. if. and the roman already know how to use them to produce very light concrete in order to mean the buildings such as the pantheon in rome that uses these the can if you put in order you will float because it's volcanic glass full of poor's and you see here you have more send the it's use it for the mixing with lime to obtain the concrete and this is the real good one he has a lot of properties and the most important one is that it's almost the last saw ready to react with...
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