Today in 1880, US Patent 227867 A was issued, an invention of Frederick W. Wiesebrock, for his “Gas-Pressure Regulator and Indicator.” There’s no Abstract, although in the description it includes this summary:

I have invented certain new and useful Improvements in Gas- Pressure Regulators and Indicators; and I do hereby declare the following to be a full, clear, and exact description of the invention; and it consists in the construction and arrangement of parts, as will be more fully described hereinafter, reference being had to the accompanying drawings, in which Figure l is a front view of my apparatus, partly in section. Fig. 2 is a view of a cask with my apparatus attached. Fig. 3 is a detail view of the same.