Combustion Apparatus (open access)

Combustion Apparatus

Patent for a combustion apparatus that will maximize the heat produced with any given amount of fuel.
Date: December 14, 1920
Creator: Anderson, Robert James
System: The Portal to Texas History
Drill-Bit-Retaining Device (open access)

Drill-Bit-Retaining Device

Patent for a new and improved “drill bit retaining devices for drills of the hammer type”(lines 12-13), including an illustration.
Date: December 14, 1915
Creator: Weiner, Rudolph S.
System: The Portal to Texas History