Egerton's effusion method

Egerton's effusion method

[¦ej·ər·tənz ə′fyü·zhən ‚meth·əd]
(thermodynamics)
A method of determining vapor pressures of solids at high temperatures, in which one measures the mass lost by effusion from a sample placed in a tightly sealed silica pot with a small hole; the pot rests at the bottom of a tube that is evacuated for several hours, and is maintained at a high temperature by a heated block of metal surrounding it.