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Removable straightening tool
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Pump pressure operated core barrel
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Method of comminuting fusible solids
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Method of producing an allotropic form of sulphur
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Method of purifying sulphur
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Method of producing purified sulphur from impure sulphur or ores containing the same in elemental form
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Method of producing purified sulphur
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Sulphur composition of diminished inflammability and process for producing same
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Mining sulfur.
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