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US1856197A
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Method of and apparatus for evacuating oil wells
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US1686475A
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Method of and apparatus for causing oil to flow through pipe lines
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US1122167A
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Spinning or twisting apparatus.
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US1033629A
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Method of and apparatus for amplifying varying electric currents.
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US992817A
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Method of amplifying electric currents.
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US1083379A
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Method of making ingots.
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US964576A
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Method of casting ingots.
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US804634A
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Stopping mechanism for elevators.
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US790323A
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Load-regulated starting and stopping device for elevators.
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US961815A
|
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Telephone relay or repeater.
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US801816A
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Combined perfecting or two-color printing-machine.
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