Iron in Old Europe

The Gelts were first in Western Europe with underground mining. They were also able metallurgists and smiths and invented the horseshoe. Their knowledge of applied physics was demonstrated in a method to make the wooden wheels of barrows 

Germanic smiths did not imitate the large-scale Roman methods for iron manufacture, but used a technique of their own, based on intensive forging of the red-hot iron lumps from small furnaces. Slag inclusions in the iron were removed and weapons and tools gained their shapes. The Germanic smiths could not manufacture swords 

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