Vignetting Attachment for Multiple-Exposure Cameras. (open access)

Vignetting Attachment for Multiple-Exposure Cameras.

Patent for a multiple exposure camera attachment that allows multiple exposures to be made on a single plate or film, blending the exposures perfectly while avoiding harsh lines. The attachment is a telescopic tubular attachment with "a plurality of apertured light ray interrupting diaphragms" (lines 77-78).
Date: April 5, 1921
Creator: Moine, Selest E.
System: The Portal to Texas History
Drainage System. (open access)

Drainage System.

Patent for a drainage system for draining wet lands and lakes.
Date: July 5, 1910
Creator: Osborne, Charles W.
System: The Portal to Texas History