Resource Type

Calculator (open access)

Calculator

Patent for a calculator which consists of semicircular device with movable pointers and number indexes printed on it that allows the pointers to be moved to different numbers to produce the answer to a math problem such as calculating the cost of goods sold by the pound in a store.
Date: December 21, 1909
Creator: Goss, George Wilson
System: The Portal to Texas History
Pump-Piston. (open access)

Pump-Piston.

Patent for an improvement on Pump-Pistons."This invention has for its object to provide a pump-piston constructed entirely of metal in order to avoid the use of packings constructed of leather or other rapidly-wearing material; and the invention consists in certain novel features of construction herinafter fully described." (Lines 15-21) Illustration is included.
Date: December 31, 1901
Creator: Kincaid, Walter H.
System: The Portal to Texas History