Densimeter
A densimeter is a device used to measure aether density.
Early densimeters were developed in the 230s at the Nordovest Institute. They were room-sized instruments that compared aether pressure against a large filtered reference tank. Portable densimeters, invented in 249, make use of low-background water collected by boreal ice cutters.
aether density is weird. it doesnt go down as the gas inside a container is released, and it somehow produces more physical force than it should