n. A device used measure the permeability of a fluid (e.g., water) through a porous material.
n. An instrument used to measure the electromagnetic permeability of a material.
The Century Dictionary and Cyclopedia
n. An instrument for the determination of the magnetic induction in iron, or the permeability, by means of the tractive force across a gap or joint in the magnetic circuit.
Word Usage
"Thomson double bridge, the Koepsel permeameter, the Duddell double projection oscillograph, the Station photometer with Lummer-Brodhun screen, the Carey-Foster bridge and others."