Electric lights
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C.
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Article
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1881
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Elsevier Science
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English
โ 56 KB
135 various nlakers were made, under the direction of tile Geological Survey of Pe,msylvania, in a snmll shaft furnace, in which it is claimed a heat sufiieient to melt steel was maintained. [7nfbrtunately, the experiments were too much restricted, both in time and number, to give reliable results;