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Combination Drill Bit and Drill Shank
Patent for "Improvements in Combination Drill-Bits and Drill-Shanks" (lines 6-7) including illustrations.
Date:
December 30, 1919
Creator:
Humason, Granville A.
System:
The Portal to Texas History
Drill-Bit.
Patent for improvement to drill-bits. The object of the invention is to provide a bit of the character described which is especially adapted for deep well drilling by the rotary process.
Date:
December 30, 1919
Creator:
Humason, Granville A.
System:
The Portal to Texas History
Conduit Electric Railway.
Patent for an underground conduit electric railway meant to propel cars. The conduit can be drained and kept dry, and a trolley attachment protects the conduit from dirt and water as well.
Date:
December 5, 1893
Creator:
de Voe, William R.
System:
The Portal to Texas History